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;">不鏽鋼焊接性能的主要表現(xiàn)</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;;">在這裡所說(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(qū)</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;">在馬氏體型不鏽鋼和部分具有馬氏體組織的鐵素體型不鏽鋼中有時(shí)會(huì)發(fā)生低溫裂紋。由於其產(chǎn)生的主要原因是氫擴(kuò)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(kuò)散，適宜地進(jìn)行預(yù)熱和焊後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;;">在奧氏體型不鏽鋼中為減輕高溫裂紋敏感性，在成分設(shè)計(jì)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(dǎo)致了低溫韌性的下降，在雙相不鏽鋼進(jìn)行焊接時(shí)，焊接接頭區(qū)域的奧氏體量減少而對(duì)韌性產(chǎn)生影響。另外隨著其中鐵素體的增加，其韌性值有顯著下降的趨勢(shì)</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)高純鐵素體型不鏽鋼的焊接接頭的韌性顯著下降的原因是由於混入碳，氮、氧的緣故。其中一些鋼的焊接接頭中的氧含量增加後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;;">而有一些鋼則是由於在保護(hù)氣體中混人了空氣，其中的氨含量增加在基體解理麵</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;;">麵上產(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;;">奧氏體型不鏽銅、鐵素體不鏽鋼和雙相不鏽鋼易發(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，由於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;;">範(fàn)圍內(nèi)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(yù)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;;">奧氏體型不鏽鋼中應(yīng)儘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;;">以上的不鏽鋼，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(zhǎng)時(shí)間受熱時(shí)，常會(huì)出現(xiàn)鋼的強(qiáng)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;;">並且伴隨著耐蝕性的降低。由於這一現(xiàn)象多見(jiàn)於加熱溫度在</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;;">由於不鏽鋼的鉻含量大多在</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(qū)間，如果焊接時(shí)控製不當(dāng)</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(qū)間停留時(shí)間過(guò)長(zhǎng)，在一些鉻含量較高的馬氏體不鏽鋼奧氏體不鏽鋼、鐵素體不鏽鋼、雙相不鏽鋼以及沉澱硬化不鏽鋼都會(huì)出現(xiàn)</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。係統(tǒng)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;;">脆化處理後，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;;">以下的衝擊韌性比未脆化低</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(shì)。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;;">範(fàn)圍內(nèi)，脆化程度冇有明顯的區(qū)彆。</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鏽鋼的可焊性較好。馬氏體型不鏽鋼，可焊性差，但馬氏體型不鏽鋼中的低碳馬氏體不鏽鋼和低碳鉻一鎳一鉬係</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(jí)</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;;">馬氏體不鏽鋼，在采取一定的工藝、技術(shù)措施後，還是可以獲得較為滿意的焊接效果</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span>