耐热不锈钢真空双频电磁约束成形  

Dual-Frequency Electromagnetic Hold Shaping for Heat Resistant Steel Parts under Vacuum

作　　者：卢百平[1] 沈军[2] 刘林[2] 傅恒志[2] 

机构地区：[1]南昌航空大学,江西南昌330063 [2]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属材料与工程》2008年第6期1103-1107,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金重大项目(59995440)资助

摘　　要：研究了真空下耐热不锈钢的双频电磁约束成形过程,建立了真空下电磁约束成形的双感应器-熔体-屏蔽罩耦合系统。结果表明:双频电磁成形中,两感应器间距增至25mm时,预热感应器基本不影响成形感应器中的磁场分布,但能独立调整熔体的温度分布,调节电磁成形系统的有效热力比。屏蔽罩与成形感应器配置合适时,有效地调节成形感应器内磁场分布,使加热区域上移,熔体的下固/液界面升高,达到电磁压力有效作用范围内,有利于过程的耦合;同时也避免对冷却介质过分加热,改善了冷却条件。合理的有效热力比仅是保证成形耦合的必要条件;更充分的条件是,产生最大静压力的液/固界面必须刚好在最大电磁压力的作用点上。最后采用双频电磁约束成形方法获得了表面质量较好的、组织定向的大宽厚比耐热不锈钢板状件。The process of dual-frequency electromagnetic hold shaping has been studied for heat resistant steel parts. A coupling system of dual-inductor, melt and shield screen condition has been first established for the electromagnetic hold shaping in vacuum. It is found that the preheating inductor does not affect the distributions of magnetic flux density and electromagnetic pressure basically under the experiment conditions and with a space of 25mm between the two inductors. At the same time, the preheating inductor can independently regulate the temperature distribution of melt in shaping inductor and increase the overheat degree of melt. The shield screen can regulate the melt temperature distribution and raise the S/L（Solid/Liquid） interface into a proper position within the shaping inductor, which causes the melt in an ideal state with vertical side face and makes the melt shaping by maximal electromagnetic pressure. The effective ratio of heat to force is a necessary condition for the coupling of electromagnetic shaping. The sufficient condition for coupling of electromagnetic shaping is that the S/L （Solid/Liquid） interface producing maximum static pressure should locate at the acting point of maximum electromagnetic pressure. At last, the heat resistant steel plate-form parts with better surface quality and directional structure have been obtained by the dual-frequency electromagnetic hold shaping.

关 键 词：双频电磁约束成形 耐热不锈钢 磁场 温度场 耦合 

分 类 号：TG142.71[一般工业技术—材料科学与工程]