【正文】 however, iron and copper atoms, Atomic radii, lattice constant, chemical properties, are more recent, is beneficial for welding. Can be seen from the physical experiment, steel and copper or copper alloy microstructure of dissimilar metal welds, mainly by α + ε phase position, atoms not fusion gap does not exist. This can indicate, steel and copper or copper alloy, can take a variety of methods of welding. Late in the crystallization of these liquid crystals were distributed in the form of α solid copper grain boundaries, and sever the link between solid grains, the binding force between the grains to be weakened so that the plastic weld metal dropped significantly, coupled with the copper and steel linear expansion coefficient and the shrinkage of large differences in the cooling weld solidification process will have a greater welding stress. Therefore, when copper weld strength steel, plastic dropped significantly, and in the welding of the stress on the fragile joints of a hot crack sites, but as long as a reasonable implementation of the welding process, mastering welding technology, can be satisfied with the Copper steel welded joints. copper and stainless steel welding technology TIG welding of copper can obtain high quality of welded joints with arc energy concentration, the protective effect is good, narrow heataffected zone, the 哈爾濱華德學(xué)院畢業(yè)設(shè)計(jì)（論文） 32 advantages of flexible operation, this method has bee a copper and copper alloy welding method, the most widely used one Species, particularly suitable in small pieces of sheet metal and welding and repair welding. TIG Welding almost can be used for all steel, nonferrous metals and alloys, welding, ideal for chemically reactive metals and their alloys. Commonly used in stainless steel, high temperature alloys, aluminum, magnesium, titanium and their alloys and difficult to dissolve in lively metal (such as zirconium, molybdenum, niobium, etc.) and welding of dissimilar metals. TIG Weld welded easy control, easy to implement singlesided welding forming, mainly used for thin plate welding or backing plate for welding. Pulse TIG welding is particularly suitable for allposition welding sheet and pipe butt weld. However, because current tungsten, arc power limited capacity is limited, resulting in weld peration depth, welding speed, TIG welding generally only used for welding thickness in 6mm following39。s day by day, has the broad application prospect, in recent years in astronautics, the petroleum chemical industry, the utility boiler, the nuclear power, the shipbuilding and other domains obtained more and more widespread application. Because the lowcarbon steel and the copper and the alloy material have the fine performance, enables them to obtain the widespread application in the industrial engineering, this inevitably must face to these two different metal connection question, the welding is the engineerig material connection one main method, therefore carries on the lowcarbon steel alloy material and the copper alloy the welding to have in the project application aspect the significant significance, may display the lowcarbon steel alloy and the copper alloy material high performance fully, 哈爾濱華德學(xué)院畢業(yè)設(shè)計(jì)（論文） 31 receives “makes the best use of things” effect, but did not have one method to the present to be able to meet the requirements. This topic attempt uses the tungsten inert gas arc welding (TIG) to the lowcarbon steel, the copper heterogeneous material to carry on the welding, provides the theory basis and the experiment foundation for the lowcarbon steel and the copper heterogeneous material welding39。s overall performance even surpasses the sole metal structure. The heterogeneous material39。 參考文獻(xiàn) [1]劉中青 . 異種材料的焊接 [Ｍ ]. 北京 :科學(xué)出版社 ,1990. [2]周振豐 . 焊接冶金與金屬焊接 [Ｍ ]. 北京 :機(jī)械工業(yè)出版社 ,1988. [3]中國機(jī)械工程學(xué)會(huì) . 焊接手冊(cè) (2)[Ｍ ]. 北京 :機(jī)械工業(yè) 出版社 ,1992. [4]顧曾迪 . 有色金屬焊接 [Ｍ ]. 北京 :機(jī)械工業(yè)出版社 ,1987. [5]宗永福 , 張德生 . 金屬材料焊接 [Ｍ ]. 北京 :機(jī)械工業(yè)出版社 ,1995. [6]黃文哲 . 焊工手冊(cè) [Ｍ ]. 北京 :機(jī)械工業(yè)出版社 ,1991. [7]李炯輝 . 焊接金相分析基礎(chǔ)與金相圖譜 [Ｍ ]. 北京 :機(jī)械工業(yè)出版社 ,2020. [8]劉會(huì)杰 . 焊接冶金與焊接性 [Ｍ ]. 北京 : 機(jī)械工業(yè)出版社 ,2020 哈爾濱華德學(xué)院畢業(yè)設(shè)計(jì)（論文） 30 附 錄 2 Now in the project many ponents need to work in the high temperature either the low temperature, the corrosive medium, the electromagic field or the radioactive environment, the nonferrous metal material39。 （ 2）通過焊接檢驗(yàn)可知，焊縫具有良好的性能，證明焊接工藝及其參數(shù)是合理的。 本章 結(jié)論 本論文通過 TIG 焊工藝對(duì)紫銅和鋼異種材料進(jìn)行焊接，為銅和低碳鋼異種材料焊接的發(fā)展提供理論依據(jù)和實(shí)驗(yàn)基礎(chǔ)。由于鋼和銅合金的種類很多，母材中有些合金元素過渡到焊縫中時(shí)，會(huì)使鋼與銅或與銅臺(tái)金的焊接性變差，所以應(yīng)選用與鋼和銅及鋼臺(tái)金均具有良好焊接性的金屬 (如鎳基焊條或鎳 銅合金焊條 )作填充材料。 從以上圖片中可以發(fā)現(xiàn)紫銅側(cè) 和鋼側(cè) 熔合的良好。強(qiáng)度、硬度高，而塑性、韌性明顯降低。有良好的韌塑性。由圖 1（ c）可見，金相組織圖為焊縫區(qū)組織圖，從圖片上看 整個(gè)焊縫基本上以柱狀形態(tài)結(jié)晶。特征表現(xiàn)為 紫銅側(cè) α 相晶粒異常長(zhǎng)大。圖 1（ b） TIG 焊（ HS201 哈爾濱華德學(xué)院畢業(yè)設(shè)計(jì)（論文） 28 焊絲）在顯微鏡下的靠近紫銅母材側(cè)的熔合線組織金相圖。 TIG 焊幾乎可用于所有鋼材、有色金屬及其合金的焊接，特別適合于化學(xué)性質(zhì)活潑的金屬及其合金。因此，當(dāng)銅鋼焊縫強(qiáng)度、塑性顯 著下降，并且焊件中存在內(nèi)應(yīng)力時(shí)，就在接頭的脆弱部位形成熱裂，但只要執(zhí)行合理的焊接工藝，熟練掌握焊接操作技術(shù)，仍能獲得滿意的銅鋼焊接接頭。這可以說明，鋼與銅或銅合金之間，可以采用各種方法進(jìn)行焊接 。鐵與 紫 銅的熔點(diǎn)、導(dǎo)熱系數(shù)、線膨脹系數(shù)等、差別較大、這是兩種材料焊接時(shí)的不利因素； 但鐵與銅的原子量、原子半徑、點(diǎn)陣常數(shù)等化學(xué)性能、又比較近，對(duì)焊接是有利的。本課題嘗試采用鎢機(jī)氬弧焊（ TIG）對(duì)低碳鋼、銅異種材料進(jìn)行焊接，為低碳鋼和銅異種材料焊接的發(fā)展提供理論依據(jù)和實(shí)驗(yàn)基礎(chǔ) 。異種材料的焊接日益受到人們的重視，具有廣闊的應(yīng)用前景，近年來在航天、石油化工、電站鍋爐、核動(dòng)力、造船及其他一些領(lǐng)域獲得越來越廣泛的應(yīng)用 。因此在現(xiàn)代工程結(jié)構(gòu)中，我們不僅需要對(duì)大量的同種材料進(jìn)行焊接，同時(shí)也需要對(duì)相當(dāng)數(shù)量的異種材料進(jìn)行焊接，在工程中及制造中采用異種材料焊接結(jié)構(gòu)，不僅能滿足不同工作條件對(duì)材質(zhì)的不同要求，而且還能節(jié)約貴重金屬，降低結(jié)構(gòu)整體成本，充分發(fā)揮不同材料的性能優(yōu)勢(shì)。JOINING 2020 (4) 1620 哈爾濱華德學(xué)院畢業(yè)設(shè)計(jì)（論文） 26 附 錄 1 現(xiàn)在工程中許多零件需要工作在高溫或低溫、腐蝕介質(zhì)、電磁場(chǎng)或放射性環(huán)境中，其中有色金屬材料的用量也比較大。 在實(shí)驗(yàn)過程中，得到了王會(huì)學(xué)、趙偉等同學(xué)的大力配合與協(xié)作，也得到了其他同學(xué)的幫助與指導(dǎo)，在此一并表示感謝。在此，向?qū)煹呐囵B(yǎng)和教育表示崇高的敬意和衷心的感謝。 哈爾濱華德學(xué)院畢業(yè)設(shè)計(jì)（論文） 23 致 謝 本文是在導(dǎo)師 楊德云老師 的悉心指導(dǎo)下 完成的，導(dǎo)師科學(xué)客觀、一絲不茍的工作態(tài)度令學(xué)生受益頗深。 （ 2）通過焊接檢驗(yàn)可知，焊縫具有良好的力學(xué)性能以及機(jī)械性能，從而證明銅與不銹鋼可以通過一些焊接方法和合理的焊接工藝將其焊接在一起，并得到性能良好的焊接接頭。 （ 1）紫銅與不銹鋼的物理性能和化學(xué)成分差異很大，銅與不銹鋼鋼焊縫易產(chǎn)生很多缺陷