摘要：<span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">不銹鋼焊接性能的主要表現</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:'Times New Roman';"><span lang="EN-US">(1)</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">高溫裂紋</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">在這里所說(shuō)的高溫裂紋是指與焊接有關(guān)的裂紋。高溫裂紋可大致分為凝固裂紋、顯微裂紋、</span><span style="font-family:'Times New Roman';"><span lang="EN-US">HAZ(</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">熱影響區</span><span style="font-family:'Times New Roman';"><span lang="EN-US">)</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">裂紋和再加熱裂紋等。</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:'Times New Roman';"><span lang="EN-US">(2)</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">低溫裂紋</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">在馬氏體型不銹鋼和部分具有馬氏體組織的鐵素體型不銹鋼中有時(shí)會(huì )發(fā)生低溫裂紋。由于其產(chǎn)生的主要原因是氫擴散、焊接接頭的約束程度以及其中的硬化組織，所以解決方法主要是在焊接過(guò)程中減少氫的擴散，適宜地進(jìn)行預熱和焊后熱處理以及減輕約束</span></span><span style="font-family:'Times New Roman';font-size:small;"> </span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">程度。</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:'Times New Roman';"><span lang="EN-US">(3)</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">焊接接頭的韌性</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">在奧氏體型不銹鋼中為減輕高溫裂紋敏感性，在成分設計上通常使其中殘存有</span><span style="font-family:'Times New Roman';"><span lang="EN-US">5% -io%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">的鐵素體。但這些鐵素體的存在導致了低溫韌性的下降，在雙相不銹鋼進(jìn)行焊接時(shí)，焊接接頭區域的奧氏體量減少而對韌性產(chǎn)生影響。另外隨著(zhù)其中鐵素體的增加，其韌性值有顯著(zhù)下降的趨勢</span><span lang="EN-US"><span style="font-family:'Times New Roman';">.</span></span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">已證實(shí)高純鐵素體型不銹鋼的焊接接頭的韌性顯著(zhù)下降的原因是由于混入碳，氮、氧的緣故。其中一些鋼的焊接接頭中的氧含量增加后生成了氯化物型夾雜，這些夾雜物成為裂紋發(fā)生源或裂紋傳播的途徑使得韌性下降</span><span style="font-family:'Times New Roman';"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">而有一些鋼則是由于在保護氣體中混人了空氣，其中的氨含量增加在基體解理面</span><span style="font-family:'Times New Roman';"><span lang="EN-US">{100}</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">面上產(chǎn)生板條狀</span><span style="font-family:'Times New Roman';"><span lang="EN-US">Cr2 N</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，基體變硬而使得韌性下降。</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:'Times New Roman';"><span lang="EN-US">(4)b</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相脆化</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">奧氏體型不銹銅、鐵素體不銹鋼和雙相不銹鋼易發(fā)生</span><span style="font-family:'Times New Roman';"><span lang="EN-US">b</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相脆化，由于組織中析出了百分之幾的</span><span style="font-family:'Times New Roman';"><span lang="EN-US">b</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相，韌性顯著(zhù)下降。</span><span style="font-family:'Times New Roman';"><span lang="EN-US">o</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相一般是在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">600</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">～</span><span style="font-family:'Times New Roman';"><span lang="EN-US">900</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">范圍內析出，尤其在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">750</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">左右*易析出。作為防止</span><span style="font-family:'Times New Roman';"><span lang="EN-US">b</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相產(chǎn)生的預防型措，</span><span style="font-family:'Times New Roman';"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">奧氏體型不銹鋼中應盡量減少鐵索體的含量。</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:'Times New Roman';"><span lang="EN-US">(5) 475</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">脆化</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">鉻含量在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">15. 5%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">以上的不銹鋼，在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">475</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">附近</span><span style="font-family:'Times New Roman';"><span lang="EN-US">(370 -540</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，長(cháng)時(shí)間受熱時(shí)，常會(huì )出現鋼的強度升高，韌性性大幅度降低</span><span style="font-family:'Times New Roman';"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">并且伴隨著(zhù)耐蝕性的降低。由于這一現象多見(jiàn)于加熱溫度在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">475</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">。</span><span style="font-family:'Times New Roman';"><span lang="EN-US">(</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">左右，因此被稱(chēng)作</span><span style="font-family:'Times New Roman';"><span lang="EN-US">475</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">脆性。</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">由于不銹鋼的鉻含量大多在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">15. 5%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">以上，焊接時(shí)的焊接熱也一定會(huì )經(jīng)過(guò)</span><span style="font-family:'Times New Roman';"><span lang="EN-US">370</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">～</span><span style="font-family:'Times New Roman';"><span lang="EN-US">540</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">這個(gè)區間，如果焊接時(shí)控制不當</span><span style="font-family:'Times New Roman';"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">370</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">～</span><span style="font-family:'Times New Roman';"><span lang="EN-US">540</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">這個(gè)區間停留時(shí)間過(guò)長(cháng)，在一些鉻含量較高的馬氏體不銹鋼奧氏體不銹鋼、鐵素體不銹鋼、雙相不銹鋼以及沉淀硬化不銹鋼都會(huì )出現</span><span style="font-family:'Times New Roman';"><span lang="EN-US">475</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">脆化。系統的研究指出</span><span style="font-family:'Times New Roman';"><span lang="EN-US">475</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">脆化處理后，鋼不僅有冷脆性，還有熱脆性</span><span style="font-family:'Times New Roman';"><span lang="EN-US">(800</span></span><span style="font-family:宋體;mso-bidi-font-family:宋體;">℃</span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">以下的沖擊韌性比未脆化低</span><span style="font-family:'Times New Roman';"><span lang="EN-US">)</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">。脆化程度隨鉻量的增加而增大，鉻含量在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">15. 5%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">以下</span><span style="font-family:'Times New Roman';"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">則無(wú)脆化趨勢。碳含量在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">0. 04%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">～</span><span style="font-family:'Times New Roman';"><span lang="EN-US">0. 28%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">范圍內，脆化程度沒(méi)有明顯的區別。</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">奧氏體和鐵素體型不銹鋼的可焊性較好。馬氏體型不銹鋼，可焊性差，但馬氏體型不銹鋼中的低碳馬氏體不銹鋼和低碳鉻一鎳一鉬系</span><span style="font-family:'Times New Roman';"><span lang="EN-US">(</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">超級</span><span style="font-family:'Times New Roman';"><span lang="EN-US">)</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">馬氏體不銹鋼，在采取一定的工藝、技術(shù)措施后，還是可以獲得較為滿(mǎn)意的焊接效果</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span>