【摘要】 对制动梁用15Mn2CrVNb钢的铸坯角部横裂纹缺陷进行了研究,研究表明铸坯角横裂纹的形成温度为870～900℃,在这一温度条件下铌、钒等碳、氮化物析出以及铁素体在奥氏体晶界析出引起的奥氏体晶界脆化是裂纹形成的内部原因,而铸坯矫直过程中内弧侧的张应力是裂纹形成的外部原因,实践表明提高连铸坯的角部温度能够有效地避免铸坯角部横裂纹的产生。更多还原

【Abstract】 The corner crack of bloom for 15Mn2CrVNb for wagon brake beam manufacturing was studied.The results showed that the formation temperature of the corner crack was near 870~900 ℃,the internal factors of the crack were the embrittlement of the austenite grain boundary caused by the compound of Nb,V and C,N and ferrite precipitation.And the external factors were the tensile stress at the straightening process of the billet casting.Based on these reasons,increasing the temperature of the bloom corner before straightening could avoid the happening of the crack effectively.更多还原