【導讀】種材料銅和不銹鋼的焊接提供理論基礎(chǔ)和試驗基礎(chǔ)。主要采用的焊接方法為鎢極。形成各種低熔點共晶體和脆性化合物，嚴重削弱了金屬在高溫時的晶間結(jié)合力。承受較大應力，焊縫易產(chǎn)生熱裂紋。近縫區(qū)不銹鋼一側(cè)易產(chǎn)生滲透裂紋，其原因。是由液態(tài)銅對鋼有滲透作用和拉應力造成的?？椌鶆颍蛔香~和紫銅熔合區(qū)過渡均勻，結(jié)合良好；紫銅與碳鋼熔合線平直，無孔洞，且Cu和Fe相互之間有一定程度擴散，熔合區(qū)為冶金結(jié)合。

　　

【正文】 . 金屬材料焊接 [Ｍ ]. 北京 :機械工業(yè)出版社 ,1995. [6]黃文哲 . 焊工手冊 [Ｍ ]. 北京 :機械工業(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 :機械工業(yè)出版社 ,2020. [8]劉會杰 . 焊接冶金與焊接性 [Ｍ ]. 北京 : 機械工業(yè)出版社 ,2020 哈爾濱華德學院畢業(yè)設(shè)計（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。s amount used is also quite big. Selects the material should be can satisfy the work requirement the exotic material, the independent employment one material cannot satisfy in the practical application frequently each kind of request. Therefore in the modern engineering structure, we not only needs to carry on the welding to the massive homogeneous materials, simultaneously also needs to carry on the welding to the considerable amount heterogeneous material, uses the heterogeneous material welding structure in the project and the manufacture, not can only satisfy the different working condition to the material quality various requirement, moreover can also save the noble metal, reduces the structure overall cost, full display different material performance superiority. In some kind of situation, the heterogeneous material structure39。s overall performance even surpasses the sole metal structure. The heterogeneous material39。s welding is valued people39。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, 哈爾濱華德學院畢業(yè)設(shè)計（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 development. Copper and steel weldability features Carbon steel and copper have good weldability. The melting point of iron and copper, thermal conductivity, linear expansion coefficient, etc, the difference is large, this is the two materials for welding of adverse factors。 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 哈爾濱華德學院畢業(yè)設(shè)計（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 Weldment . Choice of welding wires to nickel welding wire (HS201 ), and choose singleV. Test results and analysis Metallographic and analysis diagram 1 （ a ) Copper side of base metal, its anization as α solid (. a single solid), from the entire picture, not any defects, metal. Figure 1 ( b ) TIG welding ( HS201 wire) in microscopy near copper base metal side of fusion line 哈爾濱華德學院畢業(yè)設(shè)計（論文） 33 anization metallographic figure. From figure 1 ( b ) can see