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304不鏽鋼角鋼拉深會出現(xiàn)哪些問題?

日期:2025-04-28 18:34
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摘要:<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:&quot;Times New Roman&quot;;"><span lang="EN-US">304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼拉深會出現(xiàn)哪些問題?</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:&quot;Times New Roman&quot;;"><span lang="EN-US">304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼的延展率小、彈性模量</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">E</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">較大</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">硬化指數(shù)較高</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">厚向異性指數(shù)</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">r</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">值很小</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">(304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼為</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">0.9~0.11,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">軟鋼為</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">1.3~2.0).304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼材料由屈服到破裂的塑性變形階段短</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">特彆是它的塑性應(yīng)變比的加權(quán)值</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">R</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">較大</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">.304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼板拉深開裂有時(shí)發(fā)生在拉深變形之後</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">有時(shí)是在當(dāng)拉深件由凹模內(nèi)退出時(shí)立即發(fā)生</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">;</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">有時(shí)是在拉深變形後受撞擊或振動時(shí)發(fā)生</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">;</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">也有時(shí)在拉深變形後經(jīng)過一段時(shí)間的存放或在使用過程中才發(fā)生</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">本文針對</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼板拉深時(shí)產(chǎn)生缺陷的原因進(jìn)行了分析</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">並提出解決措施</span><span lang="EN-US"><span style="font-family:&quot;Times New Roman&quot;;">.</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:&quot;Times New Roman&quot;;"><span lang="EN-US">1</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、機(jī)械性能檢驗(yàn)</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:&quot;Times New Roman&quot;;"><span lang="EN-US">(1)</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">檢驗(yàn)方法:</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:&quot;Times New Roman&quot;;"><span lang="EN-US">a.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">拉伸試驗(yàn)方法。常用的標(biāo)準(zhǔn)檢驗(yàn)方法有</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">GB/T228-87</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">JISZ2201</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">JISZ2241</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">ASTM A370</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">DIN50145</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">等</span><span lang="EN-US"><span style="font-family:&quot;Times New Roman&quot;;">;</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:&quot;Times New Roman&quot;;"><span lang="EN-US">b.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">彎曲試驗(yàn)方法。常用的標(biāo)準(zhǔn)檢驗(yàn)方法有</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">GB/T232-88</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">JISZ2204</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">JISZ2248</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">ASTM E290</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">DIN50111</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">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:&quot;Times New Roman&quot;;"><span lang="EN-US">(2)</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">性能指標(biāo):考核不鏽鋼扁鋼性能的檢驗(yàn)項(xiàng)目主要為拉伸試驗(yàn)和彎曲試驗(yàn)。指標(biāo)包括屈服點(diǎn)、抗拉強(qiáng)度、延伸率及彎曲合格等項(xiàng)。</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:&quot;Times New Roman&quot;;"><span lang="EN-US">2</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、開裂形成的原因</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;mso-hansi-font-family:&quot;;">奧氏體</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼的冷作硬化指數(shù)高</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">(304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼為</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">0.34).</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">奧氏體</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼為亞穩(wěn)定型</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">在變形時(shí)會發(fā)生相變</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">誘發(fā)馬氏體相</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">馬氏體相較脆</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">因此容易發(fā)生開裂</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">在塑性變形時(shí)</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">隨著變形量的增大</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">誘發(fā)的馬氏體含量也將隨著變形量的增大而增高</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">殘餘應(yīng)力也越大</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">.</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">殘餘應(yīng)力與馬氏體含量的關(guān)係</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;mso-hansi-font-family:&quot;;">誘發(fā)的馬氏體相含量越高</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">引起的殘餘應(yīng)力也越大</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">在加工過程中也就越易開裂</span><span lang="EN-US"><span style="font-family:&quot;Times New Roman&quot;;">.</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:&quot;Times New Roman&quot;;"><span lang="EN-US">3</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、表麵劃痕形成的原因</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:&quot;Times New Roman&quot;;"><span lang="EN-US">304</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">不鏽鋼角鋼拉深件表麵出現(xiàn)劃痕主要是由於工件和模具表麵存在相對移動</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">在一定壓力的作用下</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">致使坯料與模具局部表麵直接產(chǎn)生摩擦</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">加之坯料的變形熱使坯料及金屬屑熔敷在模具表麵上</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">,</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">使工件表麵擦傷產(chǎn)生劃痕</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;mso-hansi-font-family:&quot;;"><span style="font-size:small;">進(jìn)出口不鏽鋼角鋼的定貨一般以使用中所要求的規(guī)格為主,其鋼號為相應(yīng)的碳結(jié)鋼鋼號。也即不鏽鋼角鋼除了規(guī)格號之外,冇有特定的成分和性能係列。</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;mso-hansi-font-family:&quot;;">不鏽鋼角鋼的交貨長度分定尺、倍尺兩種,國產(chǎn)不鏽鋼角鋼的定尺選擇範(fàn)圍根據(jù)規(guī)格號的不同有</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">3—9m</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">4—12m</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">4—19m</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">、</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">6—19m</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">四個(gè)範(fàn)圍。日本產(chǎn)不鏽鋼角鋼的長度選擇範(fàn)圍為</span><span style="font-family:&quot;Times New Roman&quot;;"><span lang="EN-US">6—15m</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;mso-hansi-font-family:&quot;;">。</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span lang="EN-US"><span style="font-family:&quot;Times New Roman&quot;;font-size:small;">&nbsp;</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span>

304不鏽鋼角鋼拉深會出現(xiàn)哪些問題?

304不鏽鋼角鋼的延展率小、彈性模量E較大,硬化指數(shù)較高,厚向異性指數(shù)r值很小(304不鏽鋼角鋼為0.9~0.11,軟鋼為1.3~2.0).304不鏽鋼角鋼材料由屈服到破裂的塑性變形階段短,特彆是它的塑性應(yīng)變比的加權(quán)值R較大.304不鏽鋼角鋼板拉深開裂有時(shí)發(fā)生在拉深變形之後,有時(shí)是在當(dāng)拉深件由凹模內(nèi)退出時(shí)立即發(fā)生;有時(shí)是在拉深變形後受撞擊或振動時(shí)發(fā)生;也有時(shí)在拉深變形後經(jīng)過一段時(shí)間的存放或在使用過程中才發(fā)生.本文針對304不鏽鋼角鋼板拉深時(shí)產(chǎn)生缺陷的原因進(jìn)行了分析,並提出解決措施.

1、機(jī)械性能檢驗(yàn)

(1)檢驗(yàn)方法:

a.拉伸試驗(yàn)方法。常用的標(biāo)準(zhǔn)檢驗(yàn)方法有GB/T228-87JISZ2201、JISZ2241ASTM A370、DIN50145;

b.彎曲試驗(yàn)方法。常用的標(biāo)準(zhǔn)檢驗(yàn)方法有GB/T232-88、JISZ2204、JISZ2248ASTM E290、DIN50111等。

(2)性能指標(biāo):考核不鏽鋼扁鋼性能的檢驗(yàn)項(xiàng)目主要為拉伸試驗(yàn)和彎曲試驗(yàn)。指標(biāo)包括屈服點(diǎn)、抗拉強(qiáng)度、延伸率及彎曲合格等項(xiàng)。

2、開裂形成的原因

奧氏體304不鏽鋼角鋼的冷作硬化指數(shù)高(304不鏽鋼角鋼為0.34).奧氏體304不鏽鋼角鋼為亞穩(wěn)定型,在變形時(shí)會發(fā)生相變,誘發(fā)馬氏體相.馬氏體相較脆,因此容易發(fā)生開裂.在塑性變形時(shí),隨著變形量的增大,誘發(fā)的馬氏體含量也將隨著變形量的增大而增高,殘餘應(yīng)力也越大.殘餘應(yīng)力與馬氏體含量的關(guān)係

誘發(fā)的馬氏體相含量越高,引起的殘餘應(yīng)力也越大,在加工過程中也就越易開裂.

3、表麵劃痕形成的原因

304不鏽鋼角鋼拉深件表麵出現(xiàn)劃痕主要是由於工件和模具表麵存在相對移動,在一定壓力的作用下,致使坯料與模具局部表麵直接產(chǎn)生摩擦,加之坯料的變形熱使坯料及金屬屑熔敷在模具表麵上,使工件表麵擦傷產(chǎn)生劃痕

進(jìn)出口不鏽鋼角鋼的定貨一般以使用中所要求的規(guī)格為主,其鋼號為相應(yīng)的碳結(jié)鋼鋼號。也即不鏽鋼角鋼除了規(guī)格號之外,冇有特定的成分和性能係列。

不鏽鋼角鋼的交貨長度分定尺、倍尺兩種,國產(chǎn)不鏽鋼角鋼的定尺選擇範(fàn)圍根據(jù)規(guī)格號的不同有3—9m、4—12m、4—19m、6—19m四個(gè)範(fàn)圍。日本產(chǎn)不鏽鋼角鋼的長度選擇範(fàn)圍為6—15m。

 

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