TWI260385B

TWI260385B - Sintered heat pipe and method for manufacturing the same

Info

Publication number: TWI260385B
Application number: TW094101783A
Authority: TW
Inventors: Jung-Yuan Wu; Chu-Wan Hong; Chang-Ting Lo; Ching-Tai Cheng
Original assignee: Foxconn Tech Co Ltd
Priority date: 2005-01-21
Filing date: 2005-01-21
Publication date: 2006-08-21
Also published as: US20060162907A1; TW200626858A

Abstract

A sintered heat pipe includes a tube and a capillary structure formed on the inner wall of the tube. The capillary structure formed by sintered powder includes at least three sections arranged in axis of the tube and being different in size of the powder. Method for manufacture of the sintered heat pipe includes the following steps: (1) providing the tube, and inserting a rigid mandril into the tube; (2) filling at least three types of powder into a space formed between an inner wall of the tube and the rigid mandril in turn for forming the at least three sections of the capillary structure, the size of the three types of powder increasing sequentially; (3) sintering the powder, and then drawing out the rigid mandril; (4) filling working liquid into the tube, and then vacuumizing and sealing the tube.

Description

1260385 九、發明說明：【發明所屬之技術領域】本發明涉及-種傳熱裝置及其製造方法，尤其指一種應用於電子領域之燒結式熱管及其製造方法。【先前技術】BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat transfer device and a method of manufacturing the same, and more particularly to a sintered heat pipe used in the field of electronics and a method of manufacturing the same. [Prior Art]

I前，由於熱管具有較快的傳熱速度，而廣泛應用於電子元件散熱領域。常用之熱管包括-具有—定真空度之密封管形殼體，且在殼體=没有燒結而成之結構單一的毛細結構並充有適量之工作液體，該熱广，為蒸發端而另-端為冷凝端。當鮮蒸發端受鱗，工作液體洛發汽化，蒸汽在微小壓差下流向冷凝端放出熱量後凝結成液體，液，在毛細結構之毛細力作用下回流到蒸發端，從而使熱量由熱管蒸發端迅速傳至冷凝端。然，熱管之工作性能受毛細壓力差和回流阻力、一因素之影響，該二因素隨著毛細結構之毛細孔隙之大小而變化，當毛細孔隙較小時，其具有較大毛細壓力差，可驅動凝結液體進入毛細 =構内^向蒸發端回流，但另一方面，毛細孔隙之減小使工作液體回流=摩擦力和粘滯力增大，即工作液體回流阻力增大，導致工作液體回流速度慢，易使熱管在蒸發端發生幹燒現象，而當毛細孔隙較大時，工作，體受到較小回流阻力，然，使凝結液體吸入毛細結構之毛細壓之減小，減少工作液體回流量，亦會使熱管在蒸發端發生幹燒【發明内容】本發明之目的在於提供一種毛細壓力差大、回流阻力士熱管及其製造方法。心、、°式本發明燒結式熱管包括一殼體及設於該殼體内壁之毛細結構，該毛細結構為由彼此顆粒大小不相同之粉體燒結而成至少三段式結構。Λ 本發明燒結式熱管之製造方法包括以下步驟：1)提供殼體，向其内***一硬質芯棒；2)向該殼體與硬質芯棒之間隙内依次填置粒徑遞增之至少二段粉體；3)燒結該殼體内之粉體，而後抽出硬質芯棒；$ 向殼體内填充工作液體，抽真空密封。， 6 1260385 辟植二習知技術相比，本發明燒結式熱管之毛細結構由粒徑不同之於而成，從而產生毛細孔隙不同之毛細結構，其中，較小毛‘ 流，=結構產生較大的毛細壓力差，驅動冷凝液體在毛細結構内回 :，較大毛細孔隙之毛細結構對回流工作液體產生較力，工作液體回流迅速。罕乂】口飢阻【實施方式】 11 本發明燒結式熱管具有一殼體11及形成於該殼體八金ί制ί毛爲°構，该喊體11係由導熱性能良好之材料如銅、銅鋁二鋼形/板料幾何形狀。該毛細結構由粉段12、第二毛細結構段13及第三毛細結構段u:;工醇、作液體’該工作液體選用低沸點化學性質穩定之液體如乙 ^參閱第二圖至第六圖，上述燒結式熱管可通過如下體11曰=體11，向其内***一硬質芯棒20，且保持硬質芯'棒2〇盘殼卜Λ t、線；2)向該殼體11與硬質芯棒20之間隙内依次埴置三於遞增之銅粉；3)在1咖。。左右燒結該殼體η内之銅芯棒20;4)向殼體11内填充工作液體(圖未示)，抽具王抢封，製成本發明燒結式熱管。，、八之銅叔不會洛入則次填入之銅粉中而混合，便於填置加工。 ΜΛ Ϊ述^於燒結形成毛細結構之粉體不限於銅粉，可為1他全屬於 j銅錫合金粉、歸或喊粉鮮，其燒結溫度採之^ 作相應之變化。該粉體之粒徑可根據實際需要而選擇。他用之永· 與傳統熱管相比，本發明燒結式熱管之毛細結構故體軸向呈梯度變化，其中，較小毛細孔隙之毛細結構產分大 ^，便於冷凝液體進人毛細結_且在毛細結構内進行^，日广，，，毛細結構對回流工作液體產生較二- 。如，將熱管第三毛細結構段14所在端作為‘端，= 毛細結構lx 12所《作為冷凝端，即鮮從蒸發端至冷^ 之毛細孔P«減，在冷齡第—毛細辑段12之仏絲較:】、籌 1260385 量凝結工舰雜容^从帛―毛細結構隙由A'疑^ n二結構内由冷凝端向蒸發端回流，且熱管之毛細孔 :===增，則工作液體之回流阻力遞減，回流速度增妹错讲乂"'至琚發端參與再次蒸發循環；又如，將熱管第一羊如即從^發端，第三毛細結構段14所在端作為冷凝端，毛够iiirt結構之毛細孔隙遞增，在冷凝端，由於第三冷凝駐印端毛^=鼓’輯冷驗體喊妨力較小，且從順暢地回流至蒸“表:==二動°:力:細動冷凝液體更第-毛細③獻19 再彳料、。另外，本發明燒結式熱管的換。、之毛細孔隙較小，故有較大表面積與外界進行熱交其細^細; 以上=ίί㈣料縣，纽法料專辦請。惟，神所作之等效修飾或變化，皆應==專j 【圖式簡單說明】 =一=係本發明燒結式熱管沿其轴線剖面示意圖。係本發明燒結式鮮製造流程圖。 L主要7L件符號說明】殼體 11 第一毛細結構段 13 硬質芯棒 20 第一毛細結構段第二毛細結構段係本發爾結式鮮製造過程示意圖。 12 14Before I, the heat pipe has a fast heat transfer rate and is widely used in the field of electronic component heat dissipation. The commonly used heat pipe comprises a sealed tubular casing having a constant vacuum degree, and in the casing = a single capillary structure without sintering and filled with a proper amount of working liquid, the heat is wide, and the evaporation end is another - The end is the condensation end. When the fresh evaporation end is scaled, the working liquid is vaporized, and the steam flows to the condensation end to release heat under a slight pressure difference, and then condenses into a liquid, and the liquid is returned to the evaporation end under the capillary force of the capillary structure, so that the heat is evaporated by the heat pipe. The end is quickly transferred to the condensation end. However, the working performance of the heat pipe is affected by the capillary pressure difference and the reflux resistance, which are caused by the capillary pore size of the capillary structure. When the capillary pores are small, the capillary pressure difference is large. Driving the condensed liquid into the capillary = in the structure ^ reflux to the evaporation end, but on the other hand, the reduction of the capillary pores makes the working fluid reflux = friction and viscous force increase, that is, the working fluid reflux resistance increases, resulting in the working fluid reflux speed Slow, easy to make the heat pipe dry burning phenomenon at the evaporation end, and when the capillary pores are large, the work, the body receives less backflow resistance, of course, the capillary pressure of the condensed liquid is sucked into the capillary structure, and the working fluid return flow is reduced. Further, the heat pipe may be dry-fired at the evaporation end. SUMMARY OF THE INVENTION An object of the present invention is to provide a heat pipe having a large capillary pressure difference, a reflux resistance, and a method of manufacturing the same. Heart, ° type The sintered heat pipe of the present invention comprises a casing and a capillary structure disposed on the inner wall of the casing, the capillary structure being sintered by at least three-stage structure in which powders having different particle sizes from each other are sintered. The manufacturing method of the sintered heat pipe of the present invention comprises the following steps: 1) providing a casing into which a hard mandrel is inserted; 2) sequentially filling at least two of increasing diameters in the gap between the casing and the hard mandrel Section powder; 3) Sintering the powder in the shell, and then withdrawing the hard core rod; $ filling the working liquid into the casing and vacuum-sealing. , 6 1260385 Compared with the prior art, the capillary structure of the sintered heat pipe of the present invention is formed by different particle diameters, thereby producing a capillary structure having different capillary pores, wherein the smaller hair 'flow, = structure is produced The large capillary pressure difference drives the condensed liquid back inside the capillary structure: the capillary structure of the larger capillary pores exerts a stronger force on the returning working fluid, and the working fluid returns rapidly.乂乂口口口【【【【【【【【【【【【【【【【【【【【【【【【【【【【 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 , copper and aluminum two steel / sheet geometry. The capillary structure consists of a powder segment 12, a second capillary structure segment 13 and a third capillary structure segment u:; a working alcohol, as a liquid. The working fluid is selected from a liquid having a low boiling point chemical stability, such as B. 2 to 6 In the above, the sintered heat pipe can be inserted into a hard mandrel 20 through the following body 11 body 11, and the hard core 'rod 2 〇壳、、、, line; 2) to the casing 11 and The gap between the hard core rods 20 is sequentially set to three increments of copper powder; 3) at 1 coffee. . The copper core rod 20 in the casing η is sintered to the left and right; 4) the working liquid (not shown) is filled into the casing 11, and the furnace is sealed to form the sintered heat pipe of the present invention. , and the eight bronzes will not be mixed into the copper powder filled in, which is easy to fill and process. ΜΛ ^ ^ 于于于于于于于于于于于于于于于于于于烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结烧结The particle size of the powder can be selected according to actual needs. He uses it forever. Compared with the conventional heat pipe, the capillary structure of the sintered heat pipe of the present invention has a gradient in the axial direction, wherein the capillary structure of the smaller capillary pores has a large fraction, which facilitates the condensed liquid to enter the capillary knot. In the capillary structure, ^, 广广,,, capillary structure produces a second-to-return working liquid. For example, the end of the third capillary structure section 14 of the heat pipe is taken as the 'end, = the capillary structure lx 12 is used as the condensation end, that is, the fresh capillary hole P« from the evaporation end to the cold is reduced, in the cold-aged-capillary section 12 仏较 : 】】】 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 , the return flow resistance of the working liquid decreases, and the reflux speed increases the error of the 乂" 'to the end of the hair to participate in the evaporation cycle again; for example, the first leg of the heat pipe is from the end of the ^, the end of the third capillary structure 14 At the condensing end, the capillary pores of the iiirt structure are increased. At the condensing end, due to the third condensing station end, the drums are cold, and the cold body is less squeaky and smoothly flows back to the steaming table. Two-action °: force: fine-acting condensed liquid is more - capillary 3 offering 19 again. In addition, the sintered heat pipe of the present invention has a smaller capillary pore size, so that a larger surface area is thermally exchanged with the outside world. Fine = fine; above = ίί (4) material county, New Zealand materials, please do. However, God's equivalent modification or change All should be ==Special j [Simplified description of the drawing] = one = is a schematic cross-sectional view of the sintered heat pipe of the present invention along its axis. It is a flow chart of the sintered fresh manufacturing of the present invention. L main 7L symbol description] Capillary structure section 13 Hard mandrel 20 The first capillary structure section The second capillary structure section is a schematic diagram of the present invention.

Claims

1260385 、十、申請專利範圍： ^ 1. 一種燒結式熱管，包括一殼體及設於該殼體内壁之毛細結構，其改良在於：該毛細結構為由彼此顆粒大小不相同之粉體燒結而成至少三段式結構。 2. 如申請專利範圍第1項所述之燒結式熱管，其中該粉體沿殼體軸向顆粒大小遞增或遞減。 3. —種如申請專利範圍第1項所述之燒結式熱管之製造方法，包括以下步驟：1)提供殼體，向其内***一硬質芯棒；2)向該殼體與硬質芯棒之間隙内依次填置粒徑遞增之至少三段粉體；3)燒結該殼體内之粉體，而後抽出硬質芯棒；4)向殼體内填充工作液體，抽真空密鲁封。 4. 如申請專利範圍第3項所述之燒結式熱管之製造方法，其中該粉體 . 為金屬粉體或陶瓷粉體。 5. 如申請專利範圍第4項所述之燒結式熱管之製造方法，其中該金屬粉體為銅粉或銅錫合金粉或鋁粉。1260385, X. Patent Application Range: ^ 1. A sintered heat pipe comprising a casing and a capillary structure disposed on the inner wall of the casing, the improvement being that the capillary structure is sintered by powders having different particle sizes from each other. Into a three-stage structure. 2. The sintered heat pipe according to claim 1, wherein the powder is increased or decreased in particle size along the axial direction of the casing. 3. A method of manufacturing a sintered heat pipe according to claim 1, comprising the steps of: 1) providing a housing into which a hard core rod is inserted; 2) facing the housing and the hard core rod The gap is filled with at least three stages of powder having an increasing particle diameter; 3) sintering the powder in the casing, and then extracting the hard core rod; 4) filling the working liquid into the casing, and vacuuming the seal. 4. The method for producing a sintered heat pipe according to claim 3, wherein the powder is a metal powder or a ceramic powder. 5. The method of manufacturing a sintered heat pipe according to claim 4, wherein the metal powder is copper powder or copper tin alloy powder or aluminum powder.