1294809 九、發明說明： 【發明所屬之技術領域】1294809 IX. Description of the invention: [Technical field to which the invention pertains]
TiNi基形狀記憶合金，例如：Ti5GNi5()形狀記憶合金，可以使用傳 統的銲接接合方法，如電子束、雷射銲接、電阻銲等。然而，由 於基材局部融化，於銲道熔融區易產生樹枝狀晶及殘餘應力，此 將不利於基材形狀記憶效應之保持。不同於銲接製程，使用紅外 線快速硬銲接合為一種經濟、有效的接合方法，具較低製程溫度、 _ 快速昇、降溫特性及基材不發生熔化等優點，應可作為接合TiNi 基形狀記憶合金的選項。惟填料區生成之介金屬相，將是決定接合 後基材是否具形狀記憶性質之關鍵。本發明使用金基填料進行紅 外線硬銲接合TiNi基形狀記憶合金，由於TiNi基形狀記憶合金可固溶 —定比例之金元素，且並未減損其形狀記憶性質。因此，使用金 I填料進行TiNi基形狀記憶合金的硬鋅接點，其性質將有很大的突 破。A TiNi-based shape memory alloy such as a Ti5GNi5() shape memory alloy may be a conventional solder joint method such as electron beam, laser welding, electric resistance welding or the like. However, due to partial melting of the substrate, dendrites and residual stress are easily generated in the weld zone of the bead, which is disadvantageous for the retention of the shape memory effect of the substrate. Different from the welding process, the use of infrared fast hard soldering is an economical and effective joining method. It has the advantages of lower process temperature, rapid rise and fall, and no melting of the substrate. It should be used as a bonded TiNi-based shape memory alloy. Options. However, the intermetallic phase formed in the filler zone will be the key to determining whether the substrate has shape memory properties after bonding. The present invention uses a gold-based filler for the in-line hard-welding TiNi-based shape memory alloy, since the TiNi-based shape memory alloy can solidify a proportional gold element without detracting from its shape memory property. Therefore, the use of gold I filler for the hard zinc joint of TiNi-based shape memory alloys will have a large break.
5 1294809 【先前技術】 所謂硬銲是指需在接合件工件之間使用填充合金，並升溫到填充合 金的熔點以上約10°C -1 〇〇°c後，使填充合金完全熔化並和接合件的表面產生 鍵結(bonding)的一種接合方式。由於在硬銲製程中母材並未發生熔化，僅 填料發生全熔，故此製程常被用來接合一些傳統銲接製程所無法接合的異 種材料。此製程與另一種軟録製程非常類似，區分軟銲和硬銲最簡單的方 法，就是依據其製程加以區分。通常製程溫度低於450°C的稱為軟銲，高於 450°C的稱為硬銲。故在軟銲製程中使用的填充合金大多是熔點較低的元素 如：錯(Pb)、錫(Sn)…等，其所組成填充合金之熔點較低，大多是低於45〇 °C。反觀，在硬銲製程中使用的填充合金大多由熔點較高的元素所組成， 如：銀(Ag)、銅(Cu)、鎳⑽、鈦(Ti)…等。這些銀基、銅基、鎳基或是鈦 基填充合金的熔點大多高於450°C，甚至於高達1〇〇〇。〇以上(如：部分鎳基 硬銲填充合金）。 由於硬銲是在比較高的製程溫度中進行，所以在硬銲過程中有比較 廣泛的冶金現象發生，例如：部分硬銲合金溶入基材中，或是基材中的元 素由於在高溫的環境下，藉由擴散作騎人填充合金中，因而改變了填充 合金的化學齡，躺影響填充合金的軸性及賴性，並使接合強度發 生改變，攻稱為合金化作用。此外，使用較高溫的製程也會使硬銲填充合 金，對於周圍的氣氛(特別是氧氣)比軟銲填充合金更加敏感 。故進行硬銲製 程時’在保魏氛(如：惰性氣體)或是真空下硬銲，將預期會有較佳的效果。 6 1294809 在硬輝接合製程步驟中可以簡單的分為：（1)將工件升溫到填充合金熔點以 上，使填充合金完全熔化(但不可超過基材的熔點）。（2)完全熔化的填充合金 和基材間發生冶金反應並潤濕母材。（3)利用對接基材間的間隙產生毛細流 (Capillary flow)現象，將熔融的填充合金充滿於接合面間隙之中。⑷冷卻後 即可形成硬銲接點。 傳統硬鋅接合作業因加熱速率低(約5-20°C/min)，為了減少基材暴露 於咼溫環境下所可能產生之不良影響，硬銲溫度往往設定在硬銲填料炼點 溫度以上約30〜50°C的範圍内，再持溫1 〇〜30分鐘，藉由輕微過熱之液相填 料與基材間的潤濕作用來結合兩端之基材。然而，在鈦錄基形狀記憶合金 之硬知接合製程中，由於溶融的硬銲填充合金可能會對於鈦錄基形狀記憶 合金造成合金化的效果，因而改變鈦鎳基形狀記憶合金之化學組成。此外， 由於ΤιΝι基形狀記憶合金母材内含有大量的鈦元素，而鈦元素本身又具有 相當高的活性，故於傳統之硬銲製程巾，可能會形成鈦元雜硬薛填料内 部分元素發生反應，而形成具有脆性的介金屬化合物。如此一來，不僅形 狀記憶合金本身的形狀記憶特性將喪失，其接點部分亦因變脆而易發生斷 裂無法使用，這造成目前大部分的硬銲接合製程，均無法顧於鈦鎳基形 狀記憶合金之中。 7 !2948〇9 【發明内容】 鈦錄基形狀記憶合金(TiNi-based Shape Memory Alloys)以 Ti5GNi5〇 為 代表，其之化學組成依原子比為Ti50Ni50，因其具有優良的形狀記憶性、 良好的常溫機械性質(包含強度及韌性）、優良的抗腐蝕能力…等優點，故為 一深具潛力之工程材料。所謂形狀記憶性為材料於低溫下之變形，可以利 用加熱的方式使此已變形之材料升溫至某特定溫度以上時，材料即可回復 • 原狀之特性。本發明中鈦鎳基形狀記憶合金即擁有此性質。而因鈦鎳基形 ， 狀圮憶合金，可藉由其他元素(如金、銅…等元素)之添加而改變其形狀記憶 • 性質，故本專利内所涵蓋之鈦鎳基形狀記憶合金，係泛指所有以鈦鎳成分 為主體之二元、三元或多元形狀記憶合金。 由於鈦鎳基形狀記憶合金内，可以固溶一定程度的銅或金元素，而 不會造成其形狀記舰f的喪失。此二種元素巾，又以金元素的延展性最 φ 佳，故金或以金為主的合金，應為理想的硬銲填充合金之一。此外，若能 使用快速硬銲接合餘，將造成基材(鈦職形狀記憶合金)暴露於高溫中的 時間大巾田減少，故而減低因製程高溫造成鈦鎳基形狀記憶合金的不良影 響，如：介金屬化合物之生成或母材發生合金化的可能性。不同於傳統硬 銲的加熱方式，紅外線加熱爐具極為快速的熱循環，可提供高達 3000 C/min升溫率，故為一種新型的硬銲接合製程方式。此法將可 有效抑制工件文到長期局溫所產生的不良影響。因此，使用快速硬鲜 接合製程，於硬銲接合後將能夠保有原鈦鎳基形狀記憶合金之性質，此點 8 1294809 為傳統硬銲接合製程所不及。 本發明中提出使用金基硬銲填料快速硬銲接合鈦鎳基形狀記憶合金 之方法，其特徵在於快速加熱並熔化硬銲填料後，能夠潤濕並於冷卻後接 合鈦鎳基形狀記憶合金。 1294809 【實施方式】 兹以下列實例’詳細說明本創作之具體工藝。發明中所使用的紅外 線鱗接合裝置，絲帛日本製ULVAC SINK⑽KQ 型紅外 線加熱爐體，具有六組石英燈f (内有職熱絲)與六個拋物線形之黃金聚光 反射曲面，最高工作溫度可達約· t，輸入功率卿㈣為i2kw，整體 接口系、敲於國内自雜裝而^配備有__端封口之石英倾管與其它附 •屬之進、排氣設備。而此紅外線快速加熱裝置，可在流動氬氣、保護氣氛 . 或高真空(〈SxlO^mbar)下進行紅外線硬銲製程。 • 實驗中紅外線硬銲溫度為贈C，昇溫速率設定為60(mmin，持 溫時間分別為60及180秒。實驗中使用％微米厚之純金羯片為硬鮮填料。 、·工外線硬銲接合賴絲狀記憶合金後，崎^切纖將試4切成大小為 6〇mm(長）、5mm(寬)及〇.5mm(厚)的尺寸’再進行f曲測試如圖一所示。第 籲-圖内1為Τ_5。形狀記憶合金，2為以純金硬鲜填料於接合後所形成硬 銲接點的位置。在試中，先將上述試片於低溫(液氮中)下進行弯曲至 味’再將試片升溫至室溫以量測其回復角度⑽。此時可以依下列公式計算 出回復率：5 1294809 [Prior Art] The so-called brazing refers to the use of a filler alloy between the workpieces of the joint and heating up to about 10 ° C -1 〇〇 ° c above the melting point of the filler alloy to completely melt and bond the filler alloy. The surface of the piece creates a way of bonding. Since the base metal does not melt during the brazing process, only the filler is fully melted, so the process is often used to join dissimilar materials that cannot be joined by conventional soldering processes. This process is very similar to another soft recording process. The easiest way to distinguish between soldering and brazing is to differentiate it based on its process. Generally, a process temperature lower than 450 °C is called soldering, and a temperature higher than 450 °C is called brazing. Therefore, most of the filler alloys used in the soldering process are elements with lower melting points such as (Pb), tin (Sn), etc., and the filler alloys have a low melting point, mostly below 45 °C. In contrast, the filler alloys used in the brazing process are mostly composed of elements having a higher melting point, such as silver (Ag), copper (Cu), nickel (10), titanium (Ti), and the like. The melting points of these silver-based, copper-based, nickel-based or titanium-based filler alloys are mostly above 450 ° C, even up to 1 〇〇〇. Above ( (eg partial nickel-based brazing filler alloy). Since brazing is carried out at relatively high process temperatures, a relatively wide range of metallurgical phenomena occur during brazing, for example, partial brazing alloys are dissolved in the substrate, or elements in the substrate are at high temperatures. In the environment, by diffusion as a rider filling alloy, thus changing the chemical age of the filler alloy, lying on the axial and susceptibility of the filler alloy, and changing the joint strength, called the alloying effect. In addition, the use of a higher temperature process will also result in a braze-filled alloy that is more sensitive to the surrounding atmosphere (especially oxygen) than to soft-filled alloys. Therefore, when the brazing process is carried out, it is expected to have a better effect if it is brazed under a protective atmosphere (such as inert gas) or under vacuum. 6 1294809 can be easily divided into the hard-gluing process: (1) The workpiece is heated to above the melting point of the filler alloy to completely melt the filler alloy (but not beyond the melting point of the substrate). (2) Metallurgical reaction between the completely melted filler alloy and the substrate and wetting of the base material. (3) A capillary flow phenomenon is generated by the gap between the butted substrates, and the molten filler alloy is filled in the gap of the joint surface. (4) After cooling, a hard solder joint can be formed. In the traditional hard zinc bonding operation, due to the low heating rate (about 5-20 ° C / min), in order to reduce the adverse effects that may occur when the substrate is exposed to a hot environment, the brazing temperature is often set above the brazing filler temperature. In the range of about 30 to 50 ° C, the temperature is maintained for 1 〇 to 30 minutes, and the substrate at both ends is bonded by the wetting action between the slightly superheated liquid phase filler and the substrate. However, in the hard-knit bonding process of the Titanium-based shape memory alloy, the chemical composition of the titanium-nickel-based shape memory alloy is changed because the molten braze-filled alloy may cause an alloying effect on the Titanium-based shape memory alloy. In addition, since the ΤιΝι-based shape memory alloy base material contains a large amount of titanium element, and the titanium element itself has a relatively high activity, in the conventional hard-welding process towel, some elements in the titanium-doped hard-filled Xue filler may be formed. The reaction forms a mesometallic compound having brittleness. In this way, not only the shape memory property of the shape memory alloy itself will be lost, but also the contact portion is brittle and easy to be broken, which makes most of the current hard soldering processes unable to take into account the titanium-nickel-based shape. Among the memory alloys. 7 !2948〇9 【Dissection】 TiNi-based Shape Memory Alloys are represented by Ti5GNi5〇, whose chemical composition is Ti50Ni50 according to atomic ratio, because of its excellent shape memory and good It has a potential for engineering properties such as mechanical properties at room temperature (including strength and toughness) and excellent corrosion resistance. The shape memory property is the deformation of the material at a low temperature, and the material can be restored to the original state by heating to increase the temperature of the deformed material to a certain temperature or higher. The titanium-nickel-based shape memory alloy of the present invention possesses this property. However, due to the titanium-nickel-based shape, the shape-recalling alloy can be changed by the addition of other elements (such as gold, copper, etc.), so the titanium-nickel-based shape memory alloy covered by this patent, It refers to all binary, ternary or multi-element shape memory alloys based on titanium-nickel components. Due to the titanium-nickel-based shape memory alloy, a certain degree of copper or gold element can be dissolved, without causing loss of its shape. The two elemental towels have the best ductility of gold, so gold or gold-based alloys should be one of the ideal brazing filler alloys. In addition, if the fast hard soldering balance can be used, the time for exposing the substrate (titanium shape memory alloy) to high temperature is reduced, so that the adverse effects of the titanium-nickel shape memory alloy due to the high temperature of the process are reduced, such as : The possibility of formation of a metal-containing compound or alloying of a base material. Different from the traditional hard soldering method, the infrared heating furnace has an extremely fast thermal cycle and can provide a heating rate of up to 3000 C/min, so it is a new type of hard soldering process. This method will effectively suppress the adverse effects of the workpiece text to the long-term local temperature. Therefore, the use of a fast hard and fresh bonding process will retain the properties of the original titanium-nickel-based shape memory alloy after hard soldering, which is not as good as the conventional hard soldering process. The present invention proposes a method of rapidly hard-welding a titanium-nickel-based shape memory alloy using a gold-based brazing filler, which is characterized in that after rapidly heating and melting the brazing filler, it can be wetted and bonded to a titanium-nickel-based shape memory alloy after cooling. 1294809 [Embodiment] The specific process of the present creation will be described in detail by the following examples. Infrared scale bonding device used in the invention, the U.S. ULVAC SINK (10) KQ type infrared heating furnace body has six sets of quartz lamps f (with internal hot wire) and six parabolic gold concentrating reflective surfaces, and the maximum working temperature can be used. Dayo t, input power Qing (four) for i2kw, the overall interface system, knocked on domestic self-mixed and equipped with __ end sealing quartz tilting pipe and other attached to the inlet and exhaust equipment. The infrared rapid heating device can perform an infrared hard soldering process under flowing argon, a protective atmosphere, or a high vacuum (<SxlO^mbar). • In the experiment, the infrared brazing temperature is given as C, and the heating rate is set to 60 (mmin, the holding time is 60 and 180 seconds respectively. In the experiment, the pure gold crucible with % micron thickness is used as the hard fresh filler. After the silky memory alloy is combined, the chip is cut into sizes of 6〇mm (length), 5mm (width) and 〇.5mm (thickness), and then the f-curve test is shown in Figure 1. The first call of Fig. 1 is Τ_5. Shape memory alloy, 2 is the position of the hard solder joint formed by the pure gold hard fresh filler after bonding. In the test, the test piece is firstly carried out under low temperature (liquid nitrogen) Bend to the taste' and then raise the test piece to room temperature to measure the recovery angle (10). At this time, the recovery rate can be calculated according to the following formula:
Recovery Ratio = (θ^θΓ)/θί 硬銲實驗結果顯示’經紅外線硬銲接合持溫的秒及⑽秒之試片， 其回復率均大於99%，與未經紅外線硬銲之私心形狀記憶合金母材回復 率("％)相同。表示紅外線硬銲接合後之鈦鎳基形狀記憶合金，仍然保有 1294809 相當優良之雜織㈣。耕，硬職合制姆_立舰微鏡下 觀察，銲道中並未發現任何裂紋，故可證實此鋅點具有相當之滅，並具 有工程上顧_值。第二圖為硬賴片經電子·鏡背向電子影像觀察 硬銲區生成相及ΕΡΜΑ化學組成分析之結果，由試片炼融填料區生成相 得知，大部分均為Au固溶不同Ti、Ni元素之α时Μ相為主。 雖然紅外線卿肋⑽展料，但歧肢核技術，以金 為真料接U欽錄基形狀記憶合金則為首創M吏用本技術接合後之欽錦基 形狀記憶合金’健做相t優良之雜峨，此麟使本製程料 未來應用之潛力。 上述之具體實施例是用來說明本發明之目的、特徵及功效，對於熟 悉該項聽人士而言’根據上述說晴該具體實施例作部分變更或修改’，、、 均不脫離本發明之精神麟。蝴__飾衫脫離賴作之基本精 神下’均應屬於本創作之適用範圍。 11 1294809 【圖式簡單說明】 1. 第一圖為硬銲接合試片彎曲試片示意圖。 2. 第二圖為1100oC紅外線硬銲Ti50Ni50/Au/Ti50Ni50試片SEM圖， 其中硬銲時間為（a) 60,（b) 180 sec。接合界面中各位置之ΕΡΜΑ 數據（at%)亦附於圖中。 【主要元件符號說明】 1. Ti5〇Ni5〇形狀記憶合金 2. 硬銲接點Recovery Ratio = (θ^θΓ)/θί The results of the brazing test show that the test piece with the infrared hard soldering and the temperature of the second and (10) seconds has a recovery rate of more than 99%, and the self-shape memory without infrared brazing The alloy base material recovery rate ("%) is the same. The titanium-nickel-based shape memory alloy, which represents the infrared hard soldering, still retains 1294809, which is quite excellent (4). Under the micro-mirror observation, no cracks were found in the weld bead, so it can be confirmed that the zinc point is quite extinguished and has an engineering value. The second picture shows the results of the analysis of the chemical composition of the hard-welded area by electronic and mirror back electron imaging. The phase of the smelting filler area of the test piece is known to be mostly Au-dissolved. When the element of Ni is α, the phase is dominant. Although the infrared rib (10) exhibits material, the limb-nuclear technology uses gold as the true material to connect the U-Qin-based shape memory alloy to the first M. The fine-grained shape memory alloy after the bonding of this technology is excellent. The enthusiasm, this lining makes the future potential of this process material. The specific embodiments described above are intended to illustrate the objects, features, and effects of the present invention. For those skilled in the art, the present invention may be modified or modified in part according to the above description. Spiritual Lin. The __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 11 1294809 [Simple description of the diagram] 1. The first figure is a schematic diagram of the bending test piece of the hard-welded test piece. 2. The second figure is an SEM image of a 1100oC infrared brazing Ti50Ni50/Au/Ti50Ni50 test piece, in which the brazing time is (a) 60, (b) 180 sec. The data (at%) at each location in the joint interface is also attached to the figure. [Description of main component symbols] 1. Ti5〇Ni5〇 shape memory alloy 2. Hard solder joint
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