CN111058042A - 一种螺栓表面镀锌工艺 - Google Patents

一种螺栓表面镀锌工艺 Download PDF

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CN111058042A
CN111058042A CN201911271807.8A CN201911271807A CN111058042A CN 111058042 A CN111058042 A CN 111058042A CN 201911271807 A CN201911271807 A CN 201911271807A CN 111058042 A CN111058042 A CN 111058042A
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宋伟栋
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Shaoxing Sunny High Strength Fasteners Co ltd
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    • 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
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    • 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
    • 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
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    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
    • C23C18/18—Pretreatment of the material to be coated
    • C23C18/1803—Pretreatment of the material to be coated of metallic material surfaces or of a non-specific material surfaces
    • C23C18/1806—Pretreatment of the material to be coated of metallic material surfaces or of a non-specific material surfaces by mechanical pretreatment, e.g. grinding, sanding
    • 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
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    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
    • C23C18/18—Pretreatment of the material to be coated
    • C23C18/1803—Pretreatment of the material to be coated of metallic material surfaces or of a non-specific material surfaces
    • C23C18/1824—Pretreatment of the material to be coated of metallic material surfaces or of a non-specific material surfaces by chemical pretreatment
    • 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
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
    • C23C18/31—Coating with metals
    • C23C18/38—Coating with copper
    • C23C18/40—Coating with copper using reducing agents
    • 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
    • C23C24/00—Coating starting from inorganic powder
    • C23C24/02—Coating starting from inorganic powder by application of pressure only

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Abstract

本发明涉及紧固件技术领域，尤其涉及一种螺栓表面镀锌工艺，包括以下步骤：除油除锈、打磨镀锌、镀层性能检测以及涂覆环氧涂层；优势在于：在螺栓表面形成镀锌层后再增加环氧涂层，以增加对镀锌层的保护，提高镀锌层的耐腐蚀性和耐磨性；在镀锌环节中增加检测步骤，以保证镀锌层的质量。

Description

一种螺栓表面镀锌工艺
技术领域
本发明涉及紧固件技术领域，尤其涉及一种螺栓表面镀锌工艺。
背景技术
机械镀锌是一种与电镀锌、热镀锌铁、达克罗处理不同过程的防腐镀层，在工业生产中应用非常广泛。传统的机械镀锌工艺存在镀锌层的厚度易腐蚀、不耐磨等不足。
发明内容
本发明的目的在于提供一种螺栓表面镀锌工艺，用于提高镀锌层的耐腐蚀、耐磨性。
为了实现上述目的，本发明的技术方案如下：
一种螺栓表面镀锌工艺，包括以下步骤：
S1：将螺栓放在装有除油除锈剂的容器中进行浸泡，并不断旋转抖动容器；
S2：待螺栓表面除油除锈完毕后，取出用自来水逆流冲洗1-3min；
S3：将冲洗后的螺栓进行表面打磨，并在喷砂机中进行喷砂处理，喷砂处理时间为5-15min；
S4：将喷砂处理后的螺栓投入镀覆滚筒中，加入玻璃微珠和水后转动1-2min进行除污，除污结束后放掉污水；
S5：向镀覆滚筒中加入化学镀铜液，并转动5-10min，所述化学镀铜液包括质量比重为5-15%的硫酸铜、3-8%的硫酸镍、5-10%还原剂、硫酸和水，镀铜完毕后，用自来水逆流冲洗1min；
S6:将镀铜后的螺栓重新投入另一只镀覆滚筒中，放入玻璃微珠和水，转动镀覆滚筒并均匀添加化学促进剂和锌粉，转动过程中定时取出样品进行观察和测量，直至镀锌层达到预定厚度时，停止加入化学促进剂和锌粉并停止镀覆滚筒转动；
S7：出料后用水洗净，然后用热水浸泡2min-3min，取出后采用热风风干；
S8：将风干后的螺栓浸入环氧涂液中形成环氧涂层，浸泡过程中加入纳米级聚四氟乙烯颗粒，浸泡10-20S后取出进行烘干，使得环氧涂层固化，烘干温度为200-300℃；
S9：自然冷却至室温。
进一步的，所述步骤S7后还需进行镀锌层性能检测，所述性能检测包括腐蚀性能检测：将步骤7制得的螺栓按比例取样，将样品放入浓度为17%的硫酸溶液中浸泡15min，螺栓不露出金属本色则为合格品，若样品中的合格率达到要求，否则返回步骤S3。
进一步的，所述除油除锈剂包括质量比重为15%的盐酸、2%的硫酸、0.3%的阴离子表面活性剂、0.1%的缓蚀剂及自来水。
进一步的，所述化学促成剂包括质量比重为25%的活化剂、66%的平整剂和9%的光亮剂。
进一步的，将所述步骤S9得到的螺栓套入螺纹网套进行保护。
进一步的，所述镀锌层性能检测还包括附着力性能检测：将步骤7得到的螺栓按比例取样，将样品弯曲10°-15°后观测镀锌层是否脱落，未脱落则为合格品，若脱落则返回步骤S3。
本发明的优点在于：在螺栓表面形成镀锌层后再增加环氧涂层，以增加对镀锌层的保护，提高镀锌层的耐腐蚀性和耐磨性；在镀锌环节中增加检测步骤，以保证镀锌层的质量。
具体实施方式
以下结合实施例对本发明作进一步详细描述。
本实施例提出一种螺栓表面镀锌工艺，包括以下步骤：
S1：将螺栓放在装有除油除锈剂的容器中进行浸泡，并不断旋转抖动容器，本实施例的除锈出油剂包括质量比重为15%的盐酸、2%的硫酸、0.3%的阴离子表面活性剂、0.1%的缓蚀剂及自来水，由于螺栓表面主要为矿物质防锈油，所以选取乳化分散溶解能力好的阴离子表面活性剂，另外，阴离子表面活性剂还有明显抑制酸雾的作用，缓释剂的作用是避免引起金属的过渡腐蚀，减轻氢脆现象；
S2：待螺栓表面除油除锈完毕后，取出用自来水逆流冲洗1-3min；
S3：将冲洗后的螺栓进行表面打磨，磨出螺栓表面未除去的锈渍，并在喷砂机中进行喷砂处理，喷砂处理时间为5-15min，喷砂使得螺栓表面的污渍被进一步清除，并且还能使螺栓表面变得毛糙，利于防护层的附着；
S4：将喷砂处理后的螺栓投入镀覆滚筒中，加入玻璃微珠和水后转动1-2min进行除污，以去除工件表面附着的盐类及工序周转过程中重新生成的锈渍，除污结束后放掉污水；
S5：向镀覆滚筒中加入化学镀铜液，并转动5-10min，所述化学镀铜液包括质量比重为5-15%的硫酸铜、3-8%的硫酸镍、5-10%还原剂、硫酸和水，镀铜完毕后，用自来水逆流冲洗1min，其中硫酸的作用是为了调节化学镀铜液的PH值，保证化学镀铜液位酸性，这样螺栓表面才能保持光亮；
S6:将镀铜后的螺栓重新投入另一只镀覆滚筒中，放入玻璃微珠和水，转动镀覆滚筒并均匀添加化学促进剂和锌粉，转动过程中定时取出样品进行观察和测量，直至镀锌层达到预定厚度时，停止加入化学促进剂和锌粉并停止镀覆滚筒转动，所述化学促成剂包括质量比重为25%的活化剂、66%的平整剂和9%的光亮剂，活化剂的作用是使锌粉得到活化，易于镀涂到金属表面，平整机使得镀层能够均匀，光亮剂使得镀层光滑平整；
S7：出料后用水洗净，然后用热水浸泡2min-3min，取出后采用热风风干，使得镀锌层能够得到稳定和固化，之后取样进行镀锌层性能检测，若检测不合格则返回步骤S3进行返工，这里需要主要的是，由于磨光和喷砂工序对螺栓有一定的破坏作用，若螺栓以达到报废标准，则直接报废，不得返工；
S8：将检测合格的螺栓浸入环氧涂液中形成环氧涂层，浸泡过程中加入纳米级聚四氟乙烯颗粒，浸泡10-20S后取出进行烘干，使得环氧涂层固化，烘干温度为200-300℃；
S9：自然冷却至室温。
本实施例镀锌层的性能检测包括腐蚀性能检测和附着力检测，其中腐蚀性能检测是将步骤7制得的螺栓按比例取样，将样品放入浓度为17%的硫酸溶液中浸泡15min，螺栓不露出金属本色则为合格品；附着力性能检测是将步骤7得到的螺栓按比例取样，将样品弯曲10°-15°后观测镀锌层是否脱落，未脱落则为合格品。
上述实施例仅用于解释说明本发明的构思，而非对本发明权利保护的限定，凡利用此构思对本发明进行非实质性的改动，均应落入本发明的保护范围。

Claims (6)

1.一种螺栓表面镀锌工艺，其特征在于：包括以下步骤：
S1：将螺栓放在装有除油除锈剂的容器中进行浸泡，并不断旋转抖动容器；
S2：待螺栓表面除油除锈完毕后，取出用自来水逆流冲洗1-3min；
S3：将冲洗后的螺栓进行表面打磨，并在喷砂机中进行喷砂处理，喷砂处理时间为5-15min；
S4：将喷砂处理后的螺栓投入镀覆滚筒中，加入玻璃微珠和水后转动1-2min进行除污，除污结束后放掉污水；
S5：向镀覆滚筒中加入化学镀铜液，并转动5-10min，所述化学镀铜液包括质量比重为5-15%的硫酸铜、3-8%的硫酸镍、5-10%还原剂、硫酸和水，镀铜完毕后，用自来水逆流冲洗1min；
S6:将镀铜后的螺栓重新投入另一只镀覆滚筒中，放入玻璃微珠和水，转动镀覆滚筒并均匀添加化学促进剂和锌粉，转动过程中定时取出样品进行观察和测量，直至镀锌层达到预定厚度时，停止加入化学促进剂和锌粉并停止镀覆滚筒转动；
S7：出料后用水洗净，然后用热水浸泡2min-3min，取出后采用热风风干；
S8：将风干后的螺栓浸入环氧涂液中形成环氧涂层，浸泡过程中加入纳米级聚四氟乙烯颗粒，浸泡10-20S后取出进行烘干，使得环氧涂层固化，烘干温度为200-300℃；
S9：自然冷却至室温。
2.如权利要求1所述的一种螺栓表面镀锌工艺，其特征在于：所述步骤S7后还需进行镀锌层性能检测，所述性能检测包括腐蚀性能检测：将步骤7制得的螺栓按比例取样，将样品放入浓度为17%的硫酸溶液中浸泡15min，螺栓不露出金属本色则为合格品，若样品中的合格率达到要求，否则返回步骤S3。
3.如权利要求1所述的一种螺栓表面镀锌工艺，其特征在于：所述除油除锈剂包括质量比重为15%的盐酸、2%的硫酸、0.3%的阴离子表面活性剂、0.1%的缓蚀剂及自来水。
4.如权利要求1所述的一种螺栓表面镀锌工艺，其特征在于：所述化学促成剂包括质量比重为25%的活化剂、66%的平整剂和9%的光亮剂。
5.如权利要求1所述的一种螺栓表面镀锌工艺，其特征在于：将所述步骤S9得到的螺栓套入螺纹网套进行保护。
6.如权利要求2所述的一种螺栓表面镀锌工艺，其特征在于：所述镀锌层性能检测还包括附着力性能检测：将步骤7得到的螺栓按比例取样，将样品弯曲10°-15°后观测镀锌层是否脱落，未脱落则为合格品，若脱落则返回步骤S3。
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