西安不鏽鋼板材拉深過程中開裂原因

摘要：<p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">西安</span></span><span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">不鏽鋼板材拉深過程中開裂原因</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">拉伸奧氏體不鏽鋼板材有時會出現開裂現象，而且每個現象不太一樣。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">有的是拉伸變形之後開裂；有的是從凹模內退出時就立馬開裂；有的是拉伸變形之後受到撞擊或振動時開裂；也有的是拉伸變形過後存放一段時間或使用過程中突然開裂。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">其實開裂原因主要是因為奧氏體不鏽鋼板材的延展性比較低、彈性模量</span>E<span style="font-family:宋體;">有點大，硬化指數比較高，而且從屈服到開裂的塑性變形階段比較短。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">奧氏體不鏽鋼的冷作硬化指數相對比較高，而且是亞穩定型不鏽鋼，在變形時會發生相變，形成馬氏體組織。馬氏體相性比較脆，所以容易會開裂。在塑性變形時，隨著奧氏體相變形量的增大，誘發的馬氏體相含量也會隨著變形量的增大而增多，殘餘應力也就越高。從而形成惡性循環，在拉伸過程中奧氏體不鏽鋼板材也就越容易出現開裂現象。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">其實在奧氏體不鏽鋼板材的拉伸過程中還可以采取下列預防措施：</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">可以在凹、凸模之間塗上潤滑劑，產生一層具備一定的韌性和延展性的薄膜，這對奧氏體不鏽鋼板材的拉伸效果明顯。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">可以采用白口鑄鐵作為壓邊圈磨具，錐形壓邊圈也可以使用，因為白口鑄鐵的存油性能比較好，極易產生潤滑油膜。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:"yes";mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">把奧氏體不鏽鋼板材的邊緣加工光滑些，不能有微裂缺口，這樣有效避免開裂。</span></span> </p>