SWRCH22A冷镦钢盘条拉拔断裂原因分析.pdfVIP

doi ：10.3969/j .issn.1006-110X .2016.04.009 SWRCH22A 冷镦钢盘条拉拔断裂原因分析 徐 倩 ，徐 壮 ( 天津钢铁集团有限公司技术中心，天 津 300301) [摘 要 ] 针对 SWRCH22A 冷镦钢盘条在拉拔过程中发生断裂的问题，通过对断裂试样化学成分、力学性能、金相 组织等方面进行检测，分析出产生原因是盘条金相组织存在混晶和具有不利于拉拔的魏氏组织;钢中碳质量分数为 0.21%，含量偏高，造成盘条抗拉强度较高。提出了采用将吐丝温度控制在950 ^以 下 ，辊道速度控制在0.25m/s 以 下，碳含量控制在中下限等改进措施。 [关 键 词 ] 冷镦钢 ；拉 拔 ;盘条;魏氏组织 Analysis on Causes of Fracture occurred in Drawing of SWRCH22A Cold Heading Wire Rod XU Qian and XU Zhuang (Technology Center of Tianjin Iron and Steel Group Co., Ltd., Tianjin 300301, China) Abstract Through sample inspection in terms of chemical composition, mechanical properties and metallographic structure, the causes for the fracture of SWRCH22A cold heading wire rod during draw­ ing was analyzed and defined as mixed crystal and widmanstatten structure which was detrimental to drawing in metallographic structure. Carbon mass fraction in steel was as high as 0.21%, which induced the high drawing strength of wire rod. Therefore, the authors put forward the improvement measures of controlling laying temperature under 950 益 ，roller table speed under 0.25 m/s and carbon content within medium and lower limits. Key words cold heading steel; drawing; wire rod; widmanstatten structure i 引言 下游厂家使用SWRCH22A盘条生产自攻螺钉 冷镦钢盘条是紧固件行业使用最广泛的原材 的过程分为拉拔制坯、冷镦成型、搓丝和成品螺钉 料，主要用于制造螺栓、螺母、螺钉、自攻螺钉等紧 渗碳淬火处理等四个工序。拉拔工序为6.5 m m 盘 固件，被广泛应用于机械行业、汽车制造业和建筑 条—— 机械剥壳—— 冷 拔 （5 道次)—— 椎3.12