JP5587935B2 - Sn plating material - Google Patents

Sn plating material Download PDF

Info

Publication number
JP5587935B2
JP5587935B2 JP2012083213A JP2012083213A JP5587935B2 JP 5587935 B2 JP5587935 B2 JP 5587935B2 JP 2012083213 A JP2012083213 A JP 2012083213A JP 2012083213 A JP2012083213 A JP 2012083213A JP 5587935 B2 JP5587935 B2 JP 5587935B2
Authority
JP
Japan
Prior art keywords
layer
plating
alloy
reflow
copper
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
JP2012083213A
Other languages
Japanese (ja)
Other versions
JP2013213249A (en
Inventor
宏司 原田
慶太郎 金濱
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JX Nippon Mining and Metals Corp
Original Assignee
JX Nippon Mining and Metals Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by JX Nippon Mining and Metals Corp filed Critical JX Nippon Mining and Metals Corp
Priority to JP2012083213A priority Critical patent/JP5587935B2/en
Priority to TW102102404A priority patent/TWI479052B/en
Priority to KR1020130029205A priority patent/KR101464074B1/en
Priority to CN201310103617.1A priority patent/CN103361693B/en
Publication of JP2013213249A publication Critical patent/JP2013213249A/en
Application granted granted Critical
Publication of JP5587935B2 publication Critical patent/JP5587935B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/48—After-treatment of electroplated surfaces
    • C25D5/50—After-treatment of electroplated surfaces by heat-treatment
    • C25D5/505—After-treatment of electroplated surfaces by heat-treatment of electroplated tin coatings, e.g. by melting
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
    • C23C28/02—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D only coatings only including layers of metallic material
    • C23C28/023—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D only coatings only including layers of metallic material only coatings of metal elements only
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/10—Electroplating with more than one layer of the same or of different metals
    • C25D5/12—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D7/00—Electroplating characterised by the article coated
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R13/00—Details of coupling devices of the kinds covered by groups H01R12/70 or H01R24/00 - H01R33/00
    • H01R13/02—Contact members
    • H01R13/03—Contact members characterised by the material, e.g. plating, or coating materials
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00—Electroplating: Baths therefor
    • C25D3/02—Electroplating: Baths therefor from solutions
    • C25D3/12—Electroplating: Baths therefor from solutions of nickel or cobalt
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00—Electroplating: Baths therefor
    • C25D3/02—Electroplating: Baths therefor from solutions
    • C25D3/30—Electroplating: Baths therefor from solutions of tin
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00—Electroplating: Baths therefor
    • C25D3/02—Electroplating: Baths therefor from solutions
    • C25D3/38—Electroplating: Baths therefor from solutions of copper

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrochemistry (AREA)
  • Mechanical Engineering (AREA)
  • Electroplating Methods And Accessories (AREA)

Description

本発明は、コネクタ、端子、リレ−、スイッチ等の導電性ばね材として好適であり、銅又は銅合金表面にリフロー処理を施したＳｎめっき層を有するＳｎめっき材に関する。   The present invention relates to a Sn plating material that is suitable as a conductive spring material for connectors, terminals, relays, switches, and the like and that has a Sn plating layer that has been subjected to a reflow treatment on the surface of copper or a copper alloy.

自動車用及び民生用の端子、コネクタ、電気電子機器の各種端子、コネクタ、リレー又はスイッチ等には、Ｓｎの優れた半田濡れ性、耐食性、電気接続性を生かし、銅又は銅合金の表面にＳｎめっきが施されている（特許文献１）。また、Ｓｎめっき後にＳｎの融点以上に加熱して溶融するリフロー処理が施され、密着性や外観等を向上させている。   For terminals for automobiles and consumer use, connectors, various terminals of electrical and electronic equipment, connectors, relays, switches, etc., taking advantage of Sn's excellent solder wettability, corrosion resistance, and electrical connectivity, Sn on the surface of copper or copper alloy Plating is performed (Patent Document 1). In addition, after Sn plating, a reflow process is performed by heating to a melting point of Sn or higher to improve adhesion and appearance.

上記したＳｎめっき層を有する銅材料（以下、「Ｓｎめっき材」と称する）をプレス加工してコネクタ等を製造する際、銅材料をパッドで押えるが、銅材料表面にパッドが接触することで銅材料表面のＳｎめっき層からＳｎ粉が発生し、プレス機に混入するという問題が生じていた。   When manufacturing a connector or the like by pressing the copper material having the Sn plating layer (hereinafter referred to as “Sn plating material”), the copper material is pressed by the pad, but the pad is in contact with the surface of the copper material. There has been a problem that Sn powder is generated from the Sn plating layer on the surface of the copper material and mixed into the press.

この問題に対し、本発明者は銅又は銅合金条表面のＳｎめっき層をリフロー処理した後に最表面にＣｕ−Ｓｎ合金層を部分的に露出させると、露出したＣｕ−Ｓｎ合金層が最表面のＳｎ層を保持し（ピン止めし）、Ｓｎ粉の発生を抑制することを見出し、未公開の特願２０１１−０８０３９４において、最表面に露出したＣｕ−Ｓｎ合金層の面積率を０．５〜４％とし、最表面から見て前記Ｃｕ−Ｓｎ合金層の個数を０．０３３ｍｍ2当たり１００〜９００個としたＳｎめっき材を提案した。 In response to this problem, the present inventor partially exposed the Cu-Sn alloy layer on the outermost surface after the reflow treatment of the Sn plating layer on the surface of the copper or copper alloy strip, and the exposed Cu-Sn alloy layer becomes the outermost surface. In the unpublished Japanese Patent Application No. 2011-080394, the area ratio of the Cu—Sn alloy layer exposed to the outermost surface is set to 0.5. An Sn plating material was proposed in which the number of Cu—Sn alloy layers was 100 to 900 per 0.033 mm 2 when viewed from the outermost surface.

特開２００６−２８３１４９号公報JP 2006-283149 A

本発明者が提案した上記Ｓｎめっき材はＳｎ粉の発生を抑制する上で有効であるものの、未だ改善の余地が残されている。そこで、本発明はＳｎめっき材において摩擦によるＳｎ粉の発生を抑制するための更なる改良を提供すること目的とする。   Although the Sn plating material proposed by the present inventor is effective in suppressing the generation of Sn powder, there is still room for improvement. Then, this invention aims at providing the further improvement for suppressing generation | occurrence | production of Sn powder by friction in Sn plating material.

銅又は銅合金表面のＳｎめっき層をリフロー処理すると、基材(銅又は銅合金)中のＣｕが表面のＳｎめっき層に拡散し、Ｓｎめっき層と基材との間にＣｕ−Ｓｎ合金層が形成する。特願２０１１−０８０３９４では最表面にＳｎ層よりも硬いＣｕ−Ｓｎ合金層を所定の面積率で露出させることにより、プレス加工時にパッドで最表面を保持する際に生じる擦り傷が伸張するのを抑制し、Ｓｎ粉の発生を防止することを狙っている。   When the Sn plating layer on the surface of copper or copper alloy is reflow-treated, Cu in the base material (copper or copper alloy) diffuses into the Sn plating layer on the surface, and the Cu—Sn alloy layer between the Sn plating layer and the base material Form. In Japanese Patent Application No. 2011-080394, a Cu—Sn alloy layer harder than the Sn layer is exposed at a predetermined area ratio on the outermost surface, thereby suppressing the extension of the scratches generated when the outermost surface is held by the pad during press working. And it aims at preventing generation | occurrence | production of Sn powder | flour.

しかしながら、表層の大部分を占めるＳｎめっき層自体は依然として柔らかいため、上記手段では、Ｃｕ−Ｓｎ合金層が露出していないＳｎ層部分での擦り傷は十分に抑制することができない。そのため、Ｓｎ粉の発生は避けられない。一方で、Ｃｕ−Ｓｎ合金層の露出面積を過度に高くしてしまうと、表面のＳｎめっき層が少なくなって半田濡れ性が低下するという問題が生じる。   However, since the Sn plating layer itself that occupies most of the surface layer is still soft, the above-mentioned means cannot sufficiently suppress scratches in the Sn layer portion where the Cu—Sn alloy layer is not exposed. Therefore, the generation of Sn powder is inevitable. On the other hand, when the exposed area of the Cu—Sn alloy layer is excessively increased, there is a problem that the surface Sn plating layer is reduced and solder wettability is lowered.

そこで、本発明者は半田濡れ性を保持しながらＳｎ粉の発生を効果的に抑制可能な手法について鋭意検討したところ、リフロー処理によって基材から成長したＣｕ−Ｓｎ合金層を適度に最表面に露出させることに加えて、リフロー処理後のＳｎ層中に微細なＣｕ−Ｓｎ合金粒子を分散させることが有効であることを見出した。   Therefore, the present inventor has intensively studied a method capable of effectively suppressing the generation of Sn powder while maintaining the solder wettability, and as a result, the Cu—Sn alloy layer grown from the base material by the reflow treatment is appropriately brought to the outermost surface. In addition to exposing, it was found effective to disperse fine Cu—Sn alloy particles in the Sn layer after the reflow treatment.

本発明は斯かる知見を基礎として完成したものであり、一側面において、銅又は銅合金製の基材上に直接又は下地めっきを介してリフローＳｎめっき層を有するＳｎめっき材であって、リフローＳｎめっき層は上側のＳｎ層と下側のＣｕ−Ｓｎ合金層で構成され、Ｓｎ層を断面観察したときに粒径が１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子が５０〜１０００個／μｍ2の個数密度で存在するＳｎめっき材である。 The present invention has been completed on the basis of such knowledge. In one aspect, the present invention is an Sn plating material having a reflow Sn plating layer on a copper or copper alloy base material directly or through a base plating, The Sn plating layer is composed of an upper Sn layer and a lower Cu—Sn alloy layer. When the Sn layer is observed in cross section, the Cu—Sn alloy particles having a particle diameter of 10 to 100 nm are 50 to 1000 particles / μm 2 . It is Sn plating material which exists in number density.

本発明に係るＳｎめっき材は別の一実施形態において、リフローＳｎめっき層と基材の間にＣｕ−Ｓｎ合金層を有し、最表面に露出したＣｕ−Ｓｎ合金層の面積率が０．５〜４％であり、最表面から見てＣｕ−Ｓｎ合金層の個数が０．０３３ｍｍ2当たり１００〜９００個である。 In another embodiment, the Sn plating material according to the present invention has a Cu—Sn alloy layer between the reflow Sn plating layer and the substrate, and the area ratio of the Cu—Sn alloy layer exposed on the outermost surface is 0.00. The number of Cu—Sn alloy layers is 100 to 900 per 0.033 mm 2 when viewed from the outermost surface.

本発明に係るＳｎめっき材は別の一実施形態において、Ｓｎ層を断面観察したときに粒径が１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子が４００〜８００個／μｍ2の個数密度で存在する。 In another embodiment of the Sn plating material according to the present invention, Cu—Sn alloy particles having a particle size of 10 to 100 nm are present at a number density of 400 to 800 particles / μm 2 when the Sn layer is observed in cross section.

本発明に係るＳｎめっき材は別の一実施形態において、銅又は銅合金製の基材の表面がＣｕ下地めっき層、又は、Ｎｉ及びＣｕをこの順に積層したＣｕ／Ｎｉ二層下地めっき層で被覆されており、その上にリフローＳｎめっき層を有する。   In another embodiment of the Sn plating material according to the present invention, the surface of a copper or copper alloy base material is a Cu base plating layer, or a Cu / Ni two-layer base plating layer in which Ni and Cu are laminated in this order. It is covered and has a reflow Sn plating layer on it.

本発明は別の一側面において、本発明に係るＳｎめっき材を備えた電子部品である。   In another aspect, the present invention is an electronic component including the Sn plating material according to the present invention.

本発明に係るＳｎめっき材では摩擦によって発生するＳｎ粉の量が抑制されるため、例えば、Ｓｎめっき材をプレス加工する場合、プレス金型に送り込む手前で材料を保持するパッド部分において、パッドによって削り取られるＳｎめっきが少なくなることでパッド表面に付着するＳｎ粉が少なくなり、プレス加工時にプレス機内にＳｎ粉が混入するというトラブルを防止可能である。また、本発明に係るＳｎめっき材ははんだ濡れ性にも優れている。   Since the amount of Sn powder generated by friction is suppressed in the Sn plating material according to the present invention, for example, when pressing the Sn plating material, in the pad portion that holds the material before being fed into the press mold, By reducing the amount of Sn plating that is scraped off, the amount of Sn powder adhering to the pad surface is reduced, and it is possible to prevent the trouble that Sn powder is mixed into the press machine during pressing. Moreover, the Sn plating material according to the present invention is excellent in solder wettability.

本発明の一実施形態に係るＳｎめっき材のめっき構成を表す模式図である。It is a mimetic diagram showing the plating composition of the Sn plating material concerning one embodiment of the present invention. 半田濡れ性を評価するときのｔ２を説明するための図である。It is a figure for demonstrating t2 when evaluating solder wettability. 本発明に係るＳｎめっき材（実施例１−１）について、リフローＳｎめっき層の厚み方向と平行な断面をＳＥＭ観察（倍率２０，０００）したときの写真例である。It is a photograph example when the cross section parallel to the thickness direction of a reflow Sn plating layer is observed by SEM (magnification 20,000) about Sn plating material (Example 1-1) concerning the present invention. 図３の白枠部の拡大写真である。It is an enlarged photograph of the white frame part of FIG.

以下、本発明に係るＳｎめっき材の実施形態について説明する。   Hereinafter, embodiments of the Sn plating material according to the present invention will be described.

（１）基材の組成
本発明に係るＳｎめっき材の基材としては、銅又は銅合金基材を使用することができる。例えば、銅としては純度９９．９質量％以上のタフピッチ銅や無酸素銅などが挙げられ、銅合金としては黄銅、りん青銅、ベリリウム銅、洋白、丹銅、チタン銅及びコルソン合金などが挙げられ、端子やコネクタ等の各種電子部品の要求特性に従い、適宜選択でき、何等制限されない。 (1) Composition of base material As a base material of the Sn plating material according to the present invention, a copper or copper alloy base material can be used. Examples of copper include tough pitch copper and oxygen-free copper having a purity of 99.9% by mass or more, and examples of copper alloys include brass, phosphor bronze, beryllium copper, white, red copper, titanium copper, and Corson alloy. In accordance with the required characteristics of various electronic components such as terminals and connectors, it can be selected as appropriate and is not limited at all.

（２）リフローＳｎめっき層
基材上にはリフローＳｎめっき層が形成される。リフローＳｎめっき層は、基材の表面に直接形成することができ、又は下地めっきを介して形成することができる。下地めっきとしては、リフロー処理時にＣｕがＳｎめっき層中に拡散してＣｕ−Ｓｎ合金を形成することが可能であれば特に制限はないが、典型的にはＣｕが挙げられ、これをめっきしてもよく、又はＮｉ、Ｃｕの順にめっきしてＣｕ／Ｎｉ二層下地めっきとしてもよい。 (2) Reflow Sn plating layer A reflow Sn plating layer is formed on a base material. The reflow Sn plating layer can be formed directly on the surface of the substrate, or can be formed through a base plating. The underplating is not particularly limited as long as Cu can diffuse into the Sn plating layer and form a Cu-Sn alloy during the reflow process, but typically Cu is used. Alternatively, Ni / Cu may be plated in this order to form a Cu / Ni two-layer base plating.

リフローＳｎめっき層は、例えば、脱脂及び酸洗をした基材上に、必要に応じて下地めっき層を形成した後、Ｓｎめっき層を形成し、次いでリフロー処理を施しＳｎめっき層を加熱溶融させる工程を経ることにより製造することができる。Ｓｎめっき層の形成は電気Ｓｎめっきや無電解Ｓｎめっきのような湿式めっき、或いはＣＶＤやＰＶＤのような乾式めっきにより行うことができるが、生産性、コストの観点から電気めっきが好ましい。大量生産を行う上では、リールトゥリールの連続めっきラインで上記一連の工程を実施するのが好ましい。   The reflow Sn plating layer is formed by, for example, forming a base plating layer on a degreased and pickled substrate, if necessary, forming a Sn plating layer, and then performing a reflow process to heat and melt the Sn plating layer. It can manufacture by passing through a process. The Sn plating layer can be formed by wet plating such as electric Sn plating or electroless Sn plating, or dry plating such as CVD or PVD, but electroplating is preferable from the viewpoint of productivity and cost. In mass production, the above-described series of steps are preferably performed on a reel-to-reel continuous plating line.

Ｓｎめっき層に対してリフロー処理を施すと、Ｓｎめっき層が溶融して、上側のＳｎ層と下側のＣｕ−Ｓｎ合金層で構成されるリフローＳｎめっき層に変化する。リフロー処理によって、基材及び／又は下地めっき中のＣｕが表面のリフローＳｎめっき層に拡散し、リフローＳｎめっき層中にＣｕ−Ｓｎ合金層が形成され、最表面にはＳｎ層が残存する。また、Ｓｎ層中に微細なＣｕ−Ｓｎ合金の粒子が析出する。図１には、本発明の一実施形態に係るＳｎめっき材のめっき構成を模式的に表している。   When the reflow treatment is performed on the Sn plating layer, the Sn plating layer is melted and changed to a reflow Sn plating layer including an upper Sn layer and a lower Cu—Sn alloy layer. By the reflow treatment, the Cu in the base material and / or the base plating diffuses into the reflow Sn plating layer on the surface, a Cu—Sn alloy layer is formed in the reflow Sn plating layer, and the Sn layer remains on the outermost surface. Further, fine Cu—Sn alloy particles are precipitated in the Sn layer. In FIG. 1, the plating structure of the Sn plating material which concerns on one Embodiment of this invention is represented typically.

（３）リフローＳｎめっき層中のＣｕ−Ｓｎ合金粒子
本発明に係るＳｎめっき材においては、リフローＳｎめっき層の厚み方向と平行な断面を観察したときに粒径が１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子がＳｎ層中に５０〜１０００個／μｍ2の個数密度で存在することが特徴の一つである。推定効果としては、Ｓｎ層中に分散した微細なＣｕ−Ｓｎ合金粒子が本来的に柔らかいリフローＳｎめっき層を強化し、耐摩耗性を向上させ、Ｓｎ粉発生を抑制する。また、微細なＣｕ−Ｓｎ合金粒子がＳｎ層の最表面近傍に多数存在することで、パッドで僅かにＳｎめっきが削り取られた際に表面に露出するＣｕ−Ｓｎ合金粒子が多数存在し、それ以上のＳｎ粉の発生を抑制する。Ｃｕ−Ｓｎ合金粒子は後述するＣｕ−Ｓｎ合金層と同様の組成を有しており、粒径が１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子の個数密度を５０〜１０００個／μｍ2に設定したのは、個数密度が少なすぎると粉落ちの抑制効果が十分に得られない一方で、多すぎると半田濡れ性に悪影響を与えるためである。粒径が１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子の個数密度は、粉落ち防止効果と半田濡れ性のバランスを考慮すると、４００〜８００個／μｍ2が好ましく、５００〜８００個／μｍ2がより好ましい。 (3) Cu—Sn alloy particles in the reflow Sn plating layer In the Sn plating material according to the present invention, Cu—Sn having a particle size of 10 to 100 nm when a cross section parallel to the thickness direction of the reflow Sn plating layer is observed. One of the characteristics is that the alloy particles are present in the Sn layer at a number density of 50 to 1000 / μm 2 . As an estimation effect, fine Cu—Sn alloy particles dispersed in the Sn layer reinforce the inherently soft reflow Sn plating layer, improve the wear resistance, and suppress the generation of Sn powder. In addition, since there are many fine Cu-Sn alloy particles in the vicinity of the outermost surface of the Sn layer, there are many Cu-Sn alloy particles exposed on the surface when the Sn plating is slightly scraped off by the pad. The generation of the above Sn powder is suppressed. The Cu—Sn alloy particles have the same composition as the Cu—Sn alloy layer described later, and the number density of the Cu—Sn alloy particles having a particle size of 10 to 100 nm is set to 50 to 1000 particles / μm 2. This is because, if the number density is too small, the powder omission suppressing effect cannot be sufficiently obtained, whereas if the number density is too large, the solder wettability is adversely affected. The number density of the Cu—Sn alloy particles having a particle size of 10 to 100 nm is preferably 400 to 800 particles / μm 2 and more preferably 500 to 800 particles / μm 2 in consideration of the balance between the powder fall prevention effect and the solder wettability. preferable.

本発明において、Ｃｕ−Ｓｎ合金粒子の個数密度は、ＦＩＢ（収束イオンビーム、Focused Ion Beam）をＳｎめっき表面より照射してエッチング加工し、加工された断面をＳＥＭにて、倍率２００００倍で２視野以上を観察し、この領域で観察されるＳｎ層中の１０〜１００ｎｍの粒径のＣｕ−Ｓｎ合金粒子数を数える事で測定する。各Ｃｕ−Ｓｎ合金粒子の粒径は当該粒子を取り囲む最小円の直径として定義する。   In the present invention, the number density of Cu—Sn alloy particles is 2 by irradiating FIB (focused ion beam) from the Sn plating surface and etching, and processing the processed cross section with an SEM at a magnification of 20000 times. It measures by observing more than a visual field and counting the number of Cu-Sn alloy particles having a particle diameter of 10 to 100 nm in the Sn layer observed in this region. The particle diameter of each Cu-Sn alloy particle is defined as the diameter of the smallest circle surrounding the particle.

Ｓｎ層中の粒径が１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子の個数密度は、リフロー処理後の冷却速度が大きな影響を与える。一般には、冷却速度が速いと、Ｓｎ層中に析出するＣｕ−Ｓｎ粒子の個数が少なくなる傾向にあり、冷却速度が遅いと、Ｓｎ層中に析出するＣｕ−Ｓｎ粒子の個数が多くなる。材料がリフロー炉から出てきた直後に水冷された場合には冷却速度が速すぎるので、空冷、あるいはリフロー炉から出てきて数秒間空冷した後に水冷することが好ましい。この際、空冷領域において冷却風を送り込むファンの周波数を変化させることで冷却速度を調整することができる。   The number density of Cu—Sn alloy particles having a particle size of 10 to 100 nm in the Sn layer is greatly affected by the cooling rate after the reflow treatment. In general, when the cooling rate is high, the number of Cu—Sn particles precipitated in the Sn layer tends to decrease, and when the cooling rate is low, the number of Cu—Sn particles precipitated in the Sn layer increases. When the material is cooled with water immediately after coming out of the reflow furnace, the cooling rate is too fast. Therefore, it is preferable that the material is cooled by air or after cooling out for several seconds after coming out of the reflow furnace. At this time, the cooling rate can be adjusted by changing the frequency of the fan that sends the cooling air in the air cooling region.

（４）Ｃｕ−Ｓｎ合金層
Ｃｕ−Ｓｎ合金層は、通常はＣｕ6Ｓｎ5及び／又はＣｕ3Ｓｎ4の組成を有しているが、上記した下地めっきの成分や、基材を銅合金としたときの合金元素を含んでもよい。Ｃｕ−Ｓｎ合金層はＳｎ層よりも硬いことから、Ｓｎめっき材の最表面に部分的に露出することにより、リフローＳｎめっき層で発生した擦り傷の伝搬を阻止するので（ピン留め効果）、Ｓｎ粉の発生を抑制する効果が得られる。最表面に露出したＣｕ−Ｓｎ合金層の面積率は、低すぎるとＣｕ−Ｓｎ合金層によるピン留め効果が生じない一方で、高すぎると表面のＳｎ量が少なくなって半田濡れ性、耐食性、電気接続性等が劣化すると共に、表面が鮫肌状となって外観も劣るようになることから、０．５〜４％とするのが好ましく、１〜４％とするのがより好ましい。 (4) Cu—Sn alloy layer The Cu—Sn alloy layer usually has a composition of Cu 6 Sn 5 and / or Cu 3 Sn 4. The alloy element may be included. Since the Cu—Sn alloy layer is harder than the Sn layer, it is partially exposed on the outermost surface of the Sn plating material, thereby preventing the propagation of scratches generated in the reflow Sn plating layer (pinning effect). The effect of suppressing the generation of powder is obtained. If the area ratio of the Cu—Sn alloy layer exposed on the outermost surface is too low, the pinning effect due to the Cu—Sn alloy layer does not occur, whereas if it is too high, the amount of Sn on the surface decreases and solder wettability, corrosion resistance, The electrical connectivity and the like deteriorate, and the surface becomes rusted and the appearance is inferior, so 0.5 to 4% is preferable, and 1 to 4% is more preferable.

Ｃｕ−Ｓｎ合金層の面積率は以下の手順で測定することができる。まず、Ｓｎめっき材の表面の走査電子顕微鏡（ＳＥＭ）像の反射電子像を取得する。最表面に露出したＣｕ−Ｓｎ合金層は、Ｓｎに比べて暗い画像となるため、この像を２値化した後反転して白い画像に変換し、Ｃｕ−Ｓｎ合金層の面積を求めることで算出できる。（２値化は、例えばＳＥＭ装置の輝度レンジ２５５中１２０に設定する。）   The area ratio of the Cu—Sn alloy layer can be measured by the following procedure. First, a reflected electron image of a scanning electron microscope (SEM) image of the surface of the Sn plating material is acquired. The Cu—Sn alloy layer exposed on the outermost surface becomes a darker image than Sn. Therefore, after binarizing this image, it is inverted and converted into a white image, and the area of the Cu—Sn alloy layer is obtained. It can be calculated. (Binarization is set to 120 in the luminance range 255 of the SEM device, for example)

最表面に露出したＣｕ−Ｓｎ合金層の面積率を単に規定するだけでは、例えば粗大なＣｕ−Ｓｎ合金層がわずかな個数露出する場合も含まれるが、この場合には、上記ピン止め効果が生じ難く、同じ面積率であっても最表面に多数のＣｕ−Ｓｎ合金層が分散している方がよい。そこで、最表面に露出したＣｕ−Ｓｎ合金層の個数を制御することが望ましい。具体的には、最表面から見て、露出したＣｕ−Ｓｎ合金層の個数が０．０３３ｍｍ2当たり１００〜９００個であることが好ましく、２００〜９００個であることがより好ましい。上記個数が０．０３３ｍｍ2当たり１００個未満であると上記ピン留め効果が生じ難く、９００個を超えると表面のＳｎ量が少なくなって半田濡れ性、耐食性、電気接続性等が劣化すると共に、表面が鮫肌状となって外観も劣る場合がある。
なお、最表面にはＣｕ−Ｓｎ合金層以外に前述したＣｕ−Ｓｎ合金粒子も観察される場合があるが、両者を判別することは困難であることから、ここでは、両者を区別することなく、最表面に露出しているＣｕ−Ｓｎ合金粒子もＣｕ−Ｓｎ合金層として扱う。 Simply defining the area ratio of the Cu—Sn alloy layer exposed on the outermost surface includes, for example, a case where a small number of coarse Cu—Sn alloy layers are exposed. In this case, the pinning effect is It is hard to occur, and it is better that a large number of Cu—Sn alloy layers are dispersed on the outermost surface even if the area ratio is the same. Therefore, it is desirable to control the number of Cu—Sn alloy layers exposed on the outermost surface. Specifically, when viewed from the outermost surface, the number of exposed Cu—Sn alloy layers is preferably 100 to 900 per 0.033 mm 2 , and more preferably 200 to 900. When the number is less than 100 per 0.033 mm 2, the pinning effect is difficult to occur, and when it exceeds 900, the amount of Sn on the surface is reduced and solder wettability, corrosion resistance, electrical connectivity, etc. are deteriorated. The surface may be crumpled and the appearance may be inferior.
In addition to the Cu—Sn alloy layer, the above-mentioned Cu—Sn alloy particles may be observed on the outermost surface. However, since it is difficult to distinguish between the two, here, the two are not distinguished. The Cu—Sn alloy particles exposed on the outermost surface are also treated as a Cu—Sn alloy layer.

露出したＣｕ−Ｓｎ合金層の個数は、上記した反射電子像を２値化して得られる白い画像の中で、検出可能な最小面積０．２μｍ2以上の大きさで露出した部分の個数をコンピュータソフトウェアで数えて得ることができる。 The number of exposed Cu-Sn alloy layers is calculated by calculating the number of exposed portions with a minimum detectable area of 0.2 μm 2 or more in the white image obtained by binarizing the reflected electron image. You can count on the software.

最表面に露出したＣｕ−Ｓｎ合金層の面積率及び個数は主に、リフロー温度、リフロー時間、及びＳｎめっき厚の調整によって制御することができる。これらを調整することで、基材側から表面へのＣｕ−Ｓｎ合金層の成長度合を制御し、最表面に到達する（露出する）Ｃｕ−Ｓｎ合金層の面積率及び個数を制御することができる。リフロー時の炉内温度が高いほど、材料が良く加熱されてＣｕ−Ｓｎ合金層が成長しやすい。また、加熱用のファン周波数を高くすると、材料表面に吹き付ける熱風の作用により、Ｃｕ−Ｓｎ合金層の核生成が促進され、表面のＣｕ−Ｓｎ合金層の粒径が小さくなりやすい。リフロー処理前のＳｎめっき層の厚みは例示的には０．１〜５．０μｍとすることができ、リフロー処理後のリフローＳｎめっき層の厚みは例示的には０．１〜４．５μｍとすることができる。
なお、ここでいうリフローＳｎめっき層の厚みは、Ｓｎ層とＣｕ−Ｓｎ合金層の合計の厚みとして、電解式膜厚計を用いて測定した値をいう。 The area ratio and the number of Cu—Sn alloy layers exposed on the outermost surface can be controlled mainly by adjusting the reflow temperature, the reflow time, and the Sn plating thickness. By adjusting these, the growth rate of the Cu—Sn alloy layer from the substrate side to the surface can be controlled, and the area ratio and the number of Cu—Sn alloy layers reaching (exposed) the outermost surface can be controlled. it can. The higher the furnace temperature during reflow, the easier the material is heated and the Cu-Sn alloy layer grows more easily. Further, when the heating fan frequency is increased, the nucleation of the Cu—Sn alloy layer is promoted by the action of hot air blown on the material surface, and the particle size of the surface Cu—Sn alloy layer tends to be reduced. The thickness of the Sn plating layer before the reflow treatment can be illustratively 0.1 to 5.0 μm, and the thickness of the reflow Sn plating layer after the reflow treatment is illustratively 0.1 to 4.5 μm. can do.
In addition, the thickness of the reflow Sn plating layer here means the value measured using the electrolytic film thickness meter as the total thickness of the Sn layer and the Cu—Sn alloy layer.

（５）用途
本発明に係るＳｎめっき材は端子、コネクタ、リレー、及びスイッチ等の各種電子部品の材料として好適に使用できる。 (5) Applications The Sn plating material according to the present invention can be suitably used as a material for various electronic components such as terminals, connectors, relays, and switches.

以下に本発明の実施例を示すが、以下の実施例に本発明が限定されることを意図するものではない。   Examples of the present invention are shown below, but the present invention is not intended to be limited to the following examples.

（例１）
タフピッチ銅を原料とし、表１〜表５に示す元素を添加したインゴットを鋳造し、９００℃以上で厚さ１０ｍｍまで熱間圧延を行い、表面の酸化スケールを面削した後、冷間圧延と熱処理とを繰り返し、最後に最終冷間圧延で厚み０．２ｍｍの板(基材)に仕上げた。最終冷間圧延での圧延加工度を１０〜５０％とした。 (Example 1)
Casting an ingot to which the elements shown in Table 1 to Table 5 are added, using tough pitch copper as a raw material, hot rolling up to a thickness of 10 mm at 900 ° C. or higher, chamfering the oxide scale on the surface, The heat treatment was repeated, and finally, a plate (base material) having a thickness of 0.2 mm was finished by final cold rolling. The rolling degree in final cold rolling was set to 10 to 50%.

次に、この基材の表面を脱脂及び酸洗の後、電気めっき法によりＮｉめっき層、Ｃｕめっき層の順に下地めっき層を形成し、場合によってはＮｉめっきを省略、あるいはＮｉとＣｕ両方の下地めっきを省略し、次に電気めっき法によりＳｎめっき層を形成した。下地Ｎｉめっきを施す場合は硫酸浴（液温約５０℃、電流密度５Ａ／ｄｍ2）で電気めっきし、下地Ｎｉめっきの厚みを０．３μｍとした。下地Ｃｕめっきを施す場合は硫酸浴（液温約５０℃、電流密度３０Ａ／ｄｍ2）で電気めっきし、下地Ｃｕめっきの厚みを０．５μｍとした。Ｓｎめっきは、フェノールスルホン酸浴（液温約３５℃、電流密度１２Ａ／ｄｍ2）で電気めっきし、電着時間を調整することでＳｎめっき層の厚みを０．１〜５．０μｍとした。各めっき層の厚みは電解式膜厚計で測定した。 Next, after degreasing and pickling the surface of this base material, an underlying plating layer is formed in the order of a Ni plating layer and a Cu plating layer by electroplating, and in some cases, Ni plating is omitted or both Ni and Cu are omitted. The base plating was omitted, and then an Sn plating layer was formed by electroplating. When the base Ni plating was applied, electroplating was performed in a sulfuric acid bath (liquid temperature: about 50 ° C., current density: 5 A / dm 2 ), and the thickness of the base Ni plating was set to 0.3 μm. In the case of applying the base Cu plating, electroplating was performed in a sulfuric acid bath (liquid temperature: about 50 ° C., current density: 30 A / dm 2 ), and the thickness of the base Cu plating was set to 0.5 μm. For Sn plating, electroplating was performed with a phenolsulfonic acid bath (liquid temperature: about 35 ° C., current density: 12 A / dm 2 ), and the thickness of the Sn plating layer was adjusted to 0.1 to 5.0 μm by adjusting the electrodeposition time. . The thickness of each plating layer was measured with an electrolytic film thickness meter.

次に、雰囲気をＣＯ濃度１．０ｖｏｌ．％とした加熱炉中に、各試料を７秒間装入しファンから熱風を送りながらＳｎめっき層を溶融させた後、ファンから冷風を送ることにより冷却し、表面にリフロー処理を施したＳｎめっき材を得た。なお、表１〜５に示すように、リフロー条件及び冷却条件を変えた。リフローＳｎめっき層の厚みを表中に示す。リフローＳｎめっき層の厚みは、株式会社電測製のＣＴ−１型電解式膜厚計を用い、サンプル上の任意の５点について測定した平均値を測定値とした。   Next, the atmosphere was changed to a CO concentration of 1.0 vol. Each of the samples was placed in a heating furnace for 7 seconds, and the Sn plating layer was melted while sending hot air from the fan, then cooled by sending cold air from the fan, and the surface was subjected to reflow treatment Sn plating The material was obtained. In addition, as shown to Tables 1-5, the reflow conditions and the cooling conditions were changed. The thickness of the reflow Sn plating layer is shown in the table. The thickness of the reflow Sn plating layer was measured using an average value measured for any five points on the sample using a CT-1 type electrolytic film thickness meter manufactured by Dentsu Co., Ltd.

加熱リフロー条件は、加熱炉の温度とファンの周波数により調整した。加熱炉の温度及びファン周波数が高いほど、試料が良く加熱されてＣｕ−Ｓｎ合金層が成長した。加熱用のファン周波数を高くすると、材料表面に吹き付ける風の作用により、Ｃｕ−Ｓｎ合金層の核生成が促進され、Ｃｕ−Ｓｎ合金層の粒径が小さくなり、Ｓｎめっき最表面に露出する個々のＣｕ−Ｓｎ合金層の大きさが小さくなった。   The heating reflow conditions were adjusted by the temperature of the heating furnace and the frequency of the fan. The higher the temperature of the heating furnace and the fan frequency, the better the sample was heated and the Cu-Sn alloy layer grew. When the fan frequency for heating is increased, the nucleation of the Cu—Sn alloy layer is promoted by the action of the wind blowing on the material surface, the particle size of the Cu—Sn alloy layer is reduced, and the individual exposed to the outermost surface of the Sn plating The size of the Cu-Sn alloy layer was reduced.

また、冷却条件として、冷風を送るファンの周波数を変えた。冷却用のファン周波数を高くすると冷却速度が速くなり、リフローＳｎめっき層中に析出するＣｕ−Ｓｎ粒子の個数が少なくなった。冷却用のファン周波数を低くすると冷却速度が遅くなり、リフローＳｎめっき層中に析出するＣｕ−Ｓｎ粒子の個数が多くなった。なお、空冷を５秒間実施した後に、液温６０℃の冷却湯洗槽を通して冷却した。   In addition, the frequency of the fan sending the cool air was changed as the cooling condition. When the cooling fan frequency was increased, the cooling rate was increased, and the number of Cu—Sn particles deposited in the reflow Sn plating layer was reduced. When the cooling fan frequency was lowered, the cooling rate was lowered, and the number of Cu—Sn particles precipitated in the reflow Sn plating layer was increased. In addition, after performing air cooling for 5 second, it cooled through the cooling water washing tank with a liquid temperature of 60 degreeC.

このようにして得られた各Ｓｎめっき材について、諸特性の評価を行った。
（１）最表面から観察したＣｕ−Ｓｎ合金層の面積率
Ｓｎめっき材の表面の走査電子顕微鏡（ＳＥＭ）像の反射電子像を取得した。最表面に露出したＣｕ−Ｓｎ合金層は、Ｓｎに比べて暗い画像となるため、この像を２値化した後反転して白い画像に変換し、Ｃｕ−Ｓｎ合金層の面積を求めることで面積率を算出した。
２値化は、ＳＥＭ装置の輝度レンジ２５５中１２０に設定して行った。
（２）最表面から観察したＣｕ−Ｓｎ合金層の個数密度
上記した反射電子像を２値化して得られる白い画像の個数をＳＥＭに搭載されている粒子解析ソフトで数えて得た。なお、この個数は、２０００倍の倍率の面積（０．００６６ｍｍ2）につき５視野の総数をカウントし、０．０３３ｍｍ2当たりに換算した。
（３）断面から観察したＣｕ−Ｓｎ合金粒子の個数密度
Ｓｎめっき表面よりＦＩＢにてエッチング加工した断面を、ＳＥＭにて２００００倍で５視野観察し、Ｓｎ層中に観察される粒径１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子の総数をカウントして、1μｍ2当たりに換算した。ここで、粒子の粒径とは、一つの粒子を取り囲む最小円の直径とした。
なお、Ｃｕ−Ｓｎ合金粒子は、ＣｕとＳｎのみを含有することをＡＥＳ（Ａｕｇｅｒ Ｅｌｅｃｔｒｏｎ Ｓｐｅｃｔｒｏｓｃｏｐｙ：オージェ電子分光法）により確認した。
（４）Ｓｎ粉発生
Ｓｎめっき材を摩擦試験装置（スガ試験機株式会社製、スガ磨耗試験機）上に置き、試料表面にフェルトを載せ、フェルトの上に３０ｇのウェイトを荷重した状態で、フェルトを試料表面で１ｃｍの振幅で往復運動（走査距離１０ｍｍ、走査速度１３ｍｍ／ｓ、往復回数１５回）させた。往復運動後にフェルトの上にＳｎ粉の付着が認められない場合、もう一度同じ往復運動を実施して試料側のフェルト表面を観察し、Ｓｎの付着度合を目視評価した。評価基準は以下の通りである。評価が△であれば、Ｓｎ粉の発生が少なく実用上問題ないが、○や◎であればより好ましい。
◎：２回目の往復運動後、フェルトにＳｎ粉の付着が見られない。
○：１回目の往復運動後にフェルトにＳｎ粉の付着が見られず、２回目の往復運動後にフェルトにＳｎ粉の付着が薄く認められる。
△：１回目の往復運動後にフェルトにＳｎ粉の付着が薄く認められる。
×：１回目の往復運動後にフェルトにＳｎ粉の付着が濃く認められる。
（５）はんだ濡れ性
ＪＩＳ Ｃ６００６８−２−５４：２００９に従い、各試料のはんだ濡れ性を評価した。ここで、はんだ濡れ性の評価方法は、図２に示すように、溶融はんだに試料を浸漬して引き上げる際に、浸漬開始から表面張力による浮力が「０」となるまでの時間（ｔ２）を測定した。この時間が２秒以下であれば、実用上問題ない。
得られた結果を表１に示す。 Various characteristics were evaluated about each Sn plating material obtained in this way.
(1) Area ratio of Cu—Sn alloy layer observed from outermost surface A reflection electron image of a scanning electron microscope (SEM) image of the surface of the Sn plating material was obtained. The Cu—Sn alloy layer exposed on the outermost surface becomes a darker image than Sn. Therefore, after binarizing this image, it is inverted and converted into a white image, and the area of the Cu—Sn alloy layer is obtained. The area ratio was calculated.
Binarization was performed by setting 120 in the luminance range 255 of the SEM device.
(2) Number density of Cu—Sn alloy layer observed from the outermost surface The number of white images obtained by binarizing the above-described reflected electron image was obtained by counting with particle analysis software installed in the SEM. This number was calculated by counting the total number of 5 visual fields per area (0.0066 mm 2 ) at a magnification of 2000 times and converting it to 0.033 mm 2 .
(3) Number density of Cu—Sn alloy particles observed from the cross-section The cross-section etched by FIB from the Sn plating surface was observed at 50000 times with a SEM at 50000 times, and the particle size of 10 to 10 observed in the Sn layer was observed. The total number of 100 nm Cu—Sn alloy particles was counted and converted per 1 μm 2 . Here, the particle diameter of the particle is the diameter of the smallest circle surrounding one particle.
In addition, it confirmed that Cu-Sn alloy particle | grains contain only Cu and Sn by AES (Auger Electron Spectroscopy: Auger electron spectroscopy).
(4) Sn powder generation The Sn plating material is placed on a friction tester (Suga Test Instruments Co., Ltd., Suga Abrasion Tester), a felt is placed on the sample surface, and a weight of 30 g is loaded on the felt. The felt was reciprocated on the sample surface with an amplitude of 1 cm (scanning distance 10 mm, scanning speed 13 mm / s, number of reciprocations 15 times). When adhesion of Sn powder was not recognized on the felt after the reciprocating motion, the same reciprocating motion was performed once again to observe the felt surface on the sample side, and the degree of Sn adhesion was visually evaluated. The evaluation criteria are as follows. If evaluation is (triangle | delta), generation | occurrence | production of Sn powder will be few and it is satisfactory practically, but if it is (circle) and (double-circle), it is more preferable.
A: Sn powder does not adhere to the felt after the second reciprocating motion.
○: Sn powder does not adhere to the felt after the first reciprocation, and Sn powder adheres thinly to the felt after the second reciprocation.
Δ: After the first reciprocating motion, the adhesion of Sn powder to the felt is observed thinly.
X: Sn powder adheres strongly to the felt after the first reciprocation.
(5) Solder wettability According to JIS C60068-2-54: 2009, the solder wettability of each sample was evaluated. Here, as shown in FIG. 2, the solder wettability evaluation method is the time (t2) from the start of immersion until the buoyancy due to the surface tension becomes “0” when the sample is immersed in the molten solder and pulled up. It was measured. If this time is 2 seconds or less, there is no practical problem.
The obtained results are shown in Table 1.

表１より、基材として何れの銅合金を使用した場合であっても、断面Ｃｕ−Ｓｎ合金粒子の個数密度が本発明の範囲内にあるときに、Ｓｎ粉の発生を抑制する効果及び良好なはんだ濡れ性の両立が上手く達成できたことが分かる。一方、冷却時のファン周波数が高く、冷却速度が速すぎた場合には、断面Ｃｕ−Ｓｎ合金粒子の個数密度が増加せず、Ｓｎ粉の発生を抑制できなかった。また、冷却時のファン周波数が低く、冷却速度が遅すぎた場合には、断面Ｃｕ−Ｓｎ合金粒子の個数密度が過剰となり、はんだ濡れ性が悪化した。
また、比較例１−３では、Ｓｎめっき層を溶融させた後、直ちに液温６０℃の水槽に通すことによって試料を冷却したために、冷却速度が速すぎたことから、断面Ｃｕ−Ｓｎ合金粒子が十分に析出しなかった。そのため、Ｓｎ粉の発生が多くなった。 From Table 1, even when any copper alloy is used as the substrate, when the number density of the cross-sectional Cu-Sn alloy particles is within the range of the present invention, the effect of suppressing the generation of Sn powder and good It can be seen that a good balance of solder wettability was successfully achieved. On the other hand, when the fan frequency during cooling was high and the cooling rate was too fast, the number density of the cross-sectional Cu—Sn alloy particles did not increase, and the generation of Sn powder could not be suppressed. Moreover, when the fan frequency at the time of cooling was low and the cooling rate was too slow, the number density of the cross-sectional Cu—Sn alloy particles became excessive, and the solder wettability deteriorated.
Moreover, in Comparative Example 1-3, since the sample was cooled by immediately passing it through a water bath at a liquid temperature of 60 ° C. after the Sn plating layer was melted, the cooling rate was too high, so that the cross-sectional Cu—Sn alloy particles Did not fully precipitate. Therefore, generation | occurrence | production of Sn powder increased.

（例２）
表２〜表５に記載される添加元素を添加した各種銅合金を母材とし、表に記載される条件以外は例１と同様の条件で試料を作製して評価した結果を表２〜５に示す。 (Example 2)
Tables 2 to 5 show the results obtained by preparing and evaluating samples under the same conditions as in Example 1 except that the various copper alloys to which the additive elements described in Tables 2 to 5 are added are used as base materials. Shown in

表２〜５より、基材として何れの銅合金あるいは銅を使用した場合であっても、断面Ｃｕ−Ｓｎ合金粒子の個数密度が本発明の範囲内にあるときに、Ｓｎ粉の発生を抑制する効果及び良好なはんだ濡れ性の両立が上手く達成できたことが分かる。一方、冷却時のファン周波数が高く、冷却速度が速すぎた場合には、断面Ｃｕ−Ｓｎ合金粒子の個数密度が増加せず、Ｓｎ粉の発生を抑制できなかった。また、冷却時のファン周波数が低く、冷却速度が遅すぎた場合には、断面Ｃｕ−Ｓｎ合金粒子の個数密度が過剰となり、はんだ濡れ性が悪化した。   From Tables 2 to 5, even if any copper alloy or copper is used as the base material, the generation of Sn powder is suppressed when the number density of the cross-sectional Cu-Sn alloy particles is within the scope of the present invention. It can be seen that the effect of soldering and good solder wettability were successfully achieved. On the other hand, when the fan frequency during cooling was high and the cooling rate was too fast, the number density of the cross-sectional Cu—Sn alloy particles did not increase, and the generation of Sn powder could not be suppressed. Moreover, when the fan frequency at the time of cooling was low and the cooling rate was too slow, the number density of the cross-sectional Cu—Sn alloy particles became excessive, and the solder wettability deteriorated.

１０ Ｓｎめっき材
１１ 基材
１２ Ｃｕ−Ｓｎ合金層
１３ Ｓｎ層
１３ａ 最表面に露出したＣｕ−Ｓｎ合金層
１４ Ｃｕ−Ｓｎ合金粒子
１５ リフローＳｎめっき層
１６ Ｎｉ下地めっき層
１７ Ｃｕ下地めっき層 DESCRIPTION OF SYMBOLS 10 Sn plating material 11 Base material 12 Cu-Sn alloy layer 13 Sn layer 13a Cu-Sn alloy layer exposed on the outermost surface 14 Cu-Sn alloy particle 15 Reflow Sn plating layer 16 Ni undercoat layer 17 Cu undercoat layer

Claims (5)

銅又は銅合金製の基材上に直接又は下地めっきを介してリフローＳｎめっき層を有するＳｎめっき材であって、リフローＳｎめっき層は上側のＳｎ層と下側のＣｕ−Ｓｎ合金層で構成され、Ｓｎ層を断面観察したときに粒径が１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子が５０〜１０００個／μｍ2の個数密度で存在するＳｎめっき材。 An Sn plating material having a reflow Sn plating layer on a copper or copper alloy base material directly or through a base plating, wherein the reflow Sn plating layer is composed of an upper Sn layer and a lower Cu-Sn alloy layer An Sn plating material in which Cu—Sn alloy particles having a particle diameter of 10 to 100 nm are present at a number density of 50 to 1000 particles / μm 2 when the Sn layer is observed in cross section. リフローＳｎめっき層の最表面に露出したＣｕ−Ｓｎ合金層の面積率が０．５〜４％であり、最表面から見てＣｕ−Ｓｎ合金層の個数が０．０３３ｍｍ2当たり１００〜９００個である請求項１に記載のＳｎめっき材。 The area ratio of the Cu—Sn alloy layer exposed on the outermost surface of the reflow Sn plating layer is 0.5 to 4%, and the number of Cu—Sn alloy layers as viewed from the outermost surface is 100 to 900 per 0.033 mm 2. The Sn plating material according to claim 1. Ｓｎ層を断面観察したときに粒径が１０〜１００ｎｍのＣｕ−Ｓｎ合金粒子が４００〜８００個／μｍ2の個数密度で存在する請求項１又は２に記載のＳｎめっき材。 3. The Sn plating material according to claim 1, wherein Cu—Sn alloy particles having a particle diameter of 10 to 100 nm are present at a number density of 400 to 800 particles / μm 2 when a cross section of the Sn layer is observed. 銅又は銅合金製の基材の表面がＣｕ下地めっき層、又は、Ｎｉ及びＣｕをこの順に積層したＣｕ／Ｎｉ二層下地めっき層で被覆されており、その上にリフローＳｎめっき層を有する請求項１〜３の何れか一項に記載のＳｎめっき材。   The surface of the base material made of copper or copper alloy is covered with a Cu underplating layer or a Cu / Ni two-layer underplating layer in which Ni and Cu are laminated in this order, and a reflow Sn plating layer is provided thereon. Item 4. The Sn plating material according to any one of Items 1 to 3. 請求項１〜４の何れか一項に記載のＳｎめっき材を備えた電子部品。   The electronic component provided with the Sn plating material as described in any one of Claims 1-4.
JP2012083213A 2012-03-30 2012-03-30 Sn plating material Active JP5587935B2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2012083213A JP5587935B2 (en) 2012-03-30 2012-03-30 Sn plating material
TW102102404A TWI479052B (en) 2012-03-30 2013-01-23 Tin plating materials
KR1020130029205A KR101464074B1 (en) 2012-03-30 2013-03-19 Sn-PLATED MATERIAL
CN201310103617.1A CN103361693B (en) 2012-03-30 2013-03-28 Sn-plated material

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2012083213A JP5587935B2 (en) 2012-03-30 2012-03-30 Sn plating material

Publications (2)

Publication Number Publication Date
JP2013213249A JP2013213249A (en) 2013-10-17
JP5587935B2 true JP5587935B2 (en) 2014-09-10

Family

ID=49363918

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2012083213A Active JP5587935B2 (en) 2012-03-30 2012-03-30 Sn plating material

Country Status (4)

Country Link
JP (1) JP5587935B2 (en)
KR (1) KR101464074B1 (en)
CN (1) CN103361693B (en)
TW (1) TWI479052B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104604036A (en) * 2012-08-31 2015-05-06 株式会社自动网络技术研究所 Plated terminal for connector, and terminal pair
JP2015225704A (en) * 2014-05-26 2015-12-14 矢崎総業株式会社 Terminal
JP6160582B2 (en) * 2014-09-11 2017-07-12 三菱マテリアル株式会社 Tin-plated copper alloy terminal material and manufacturing method thereof
JP5984980B2 (en) * 2015-02-24 2016-09-06 Ｊｘ金属株式会社 Sn plating material for electronic parts

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5614328A (en) * 1995-01-19 1997-03-25 The Furukawa Electric Co. Ltd. Reflow-plated member and a manufacturing method therefor
JP4308931B2 (en) * 1997-11-04 2009-08-05 三菱伸銅株式会社 Sn or Sn alloy-plated copper alloy thin plate and connector manufactured with the thin plate
JP2000169995A (en) * 1998-09-28 2000-06-20 Nippon Mining & Metals Co Ltd Metallic material
DE19963385C1 (en) * 1999-12-28 2001-01-25 Federal Mogul Wiesbaden Gmbh Composite material layer for sliding bearings has a sliding layer made of a tin matrix in which tin-copper particles are embedded
JP3874621B2 (en) * 2001-03-30 2007-01-31 株式会社神戸製鋼所 Sn-plated copper alloy material for mating type connection terminals and mating type connection terminals
JP3880877B2 (en) * 2002-03-29 2007-02-14 Ｄｏｗａホールディングス株式会社 Plated copper or copper alloy and method for producing the same
US7820303B2 (en) * 2004-09-10 2010-10-26 Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) Conductive material for connecting part and method for manufacturing the conductive material
JP4024244B2 (en) * 2004-12-27 2007-12-19 株式会社神戸製鋼所 Conductive material for connecting parts and method for manufacturing the same
JP3926355B2 (en) * 2004-09-10 2007-06-06 株式会社神戸製鋼所 Conductive material for connecting parts and method for manufacturing the same
JP2006283149A (en) * 2005-04-01 2006-10-19 Nikko Kinzoku Kk Surface treatment method for copper or copper alloy, surface-treated material, and electronic component using the same
JP5319101B2 (en) * 2007-10-31 2013-10-16 Ｊｘ日鉱日石金属株式会社 Sn plating material for electronic parts
JP4611419B2 (en) * 2008-12-26 2011-01-12 Ｊｘ日鉱日石金属株式会社 Copper alloy tin plating strip with excellent solder wettability and insertability
JP4987028B2 (en) * 2009-03-31 2012-07-25 Ｊｘ日鉱日石金属株式会社 Copper alloy tin plating material for printed circuit board terminals
JP5419594B2 (en) * 2009-08-24 2014-02-19 株式会社神戸製鋼所 Copper or copper alloy material with tin plating for connection parts used for connection with aluminum conductive members
JP5389097B2 (en) * 2011-03-31 2014-01-15 Ｊｘ日鉱日石金属株式会社 Sn plating material
JP6103811B2 (en) * 2012-03-30 2017-03-29 株式会社神戸製鋼所 Conductive material for connecting parts

Also Published As

Publication number Publication date
TWI479052B (en) 2015-04-01
JP2013213249A (en) 2013-10-17
KR101464074B1 (en) 2014-11-21
CN103361693A (en) 2013-10-23
TW201339374A (en) 2013-10-01
CN103361693B (en) 2016-02-17
KR20130111316A (en) 2013-10-10

Similar Documents

Publication Publication Date Title
TWI330202B (en) Copper alloy sheet material for electric and electronic parts
CN103227369B (en) Tinplated copper alloy terminal material and the manufacture method thereof of plug property excellence
JP5319101B2 (en) Sn plating material for electronic parts
JP6160582B2 (en) Tin-plated copper alloy terminal material and manufacturing method thereof
JP4629154B1 (en) Copper alloy for electronic materials and manufacturing method thereof
US20140170436A1 (en) Tin-plated copper-alloy material for terminal having excellent insertion/extraction performance
JP5522300B1 (en) Tin-plated copper alloy terminal material excellent in insertion / extraction and manufacturing method thereof
JP5587935B2 (en) Sn plating material
JP5640922B2 (en) Tin-plated copper alloy terminal material with excellent insertability
JP2007262458A (en) WHISKER RESISTANT REFLOW Sn PLATING MATERIAL
JP2007092173A (en) Cu-Ni-Si-Zn BASED ALLOY TINNED STRIP
JP5389097B2 (en) Sn plating material
JP2007254803A (en) Titanium-copper
JP5984981B2 (en) Sn plating material for electronic parts
JP7121232B2 (en) Copper terminal material, copper terminal, and method for producing copper terminal material
JP4611419B2 (en) Copper alloy tin plating strip with excellent solder wettability and insertability
JP2005105307A (en) REFLOW-Sn-PLATED MEMBER, METHOD FOR MANUFACTURING THE MEMBER, AND COMPONENT FOR ELECTRICAL AND ELECTRONIC EQUIPMENT USING THE MEMBER
JP5409401B2 (en) Tin-plated copper alloy sheet for mating type terminal and method for manufacturing the same
JP2016141835A (en) Tinned copper alloy terminal material

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20130930

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20140128

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20140415

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20140520

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20140624

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20140724

R150 Certificate of patent or registration of utility model

Ref document number: 5587935

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

S531 Written request for registration of change of domicile

Free format text: JAPANESE INTERMEDIATE CODE: R313531

S533 Written request for registration of change of name

Free format text: JAPANESE INTERMEDIATE CODE: R313533

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

S531 Written request for registration of change of domicile

Free format text: JAPANESE INTERMEDIATE CODE: R313531

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250