Steel compositions and methods of processing for producing cold-formed and carburized components with fine-grained microstructures
    1.
    发明授权
    Steel compositions and methods of processing for producing cold-formed and carburized components with fine-grained microstructures 有权
    钢组合物和用于生产具有细晶粒微结构的冷成型和渗碳组分的加工方法

    公开(公告)号:US06312529B1

    公开(公告)日:2001-11-06

    申请号:US09402688

    申请日:1999-10-07

    IPC分类号: C22C3806

    摘要: Steel compositions and processes are described that provide optimum resistance to austenite grain coarsening in cold-formed and carburized components for automotive and machine structural applications. The steel compositions include, in weight percent, 0.1-0.3% C 150-220 ppm N and a grain refining addition selected from the group consisting of Al, V plus Al and Nb plus Al, the balance comprising iron and other alloying elements typically found in carburizing grades of steel. The steels are processed by reheating to a temperature in the vicinity of solution temperature of the least soluble species of grain refining precipitate and then hot worked. The hot-worked steel is cooled at an accelerated rate to 500° C. and then subcritically annealed, cold formed in at least one operation with intermediate anneals subcritically annealed after the last cold-forming operation, and carburized quenched and tempered (6).

    摘要翻译: 描述了用于汽车和机械结构应用的冷成型和渗碳部件中对奥氏体晶粒粗化提供最佳抗性的钢组合物和方法。 钢组合物包括重量百分比为0.1-0.3%C 150-220ppm N和选自Al,V加Al和Nb加Al的晶粒细化添加剂,余量包含铁和通常发现的其它合金元素 在渗碳等级钢。 通过再加热将晶粒加工成晶粒细化沉淀物的最不溶解物质的溶液温度附近的温度,然后热加工。 热加工钢以加速速率冷却至500℃,然后亚临界退火,在至少一次操作中冷成型,中间退火在最终冷成型操作后进行亚临界退火,并渗碳淬火回火(6)。

    Heat-treated steels with optimized toughness and method thereof
    2.
    发明授权
    Heat-treated steels with optimized toughness and method thereof 有权
    具有优化韧性的热处理钢及其方法

    公开(公告)号:US06277216B1

    公开(公告)日:2001-08-21

    申请号:US09148243

    申请日:1998-09-04

    IPC分类号: C22C3806

    摘要: Compositions and methods of processing have been developed to optimize the impact toughness of heat-treated, low-alloy steels. The disclosed ranges of steel composition provide a lightly-tempered martensitic microstructure in which grain-refining precipitate forming elements such as titanium and aluminum are essentially absent and the content of iron/alloy carbides retained through the hardening operation is minimized through the application of an appropriate heat treatment wherein austenitizing takes place at temperatures of about 900° C. or above followed by quenching and lightly tempering at about 180° C.

    摘要翻译: 已经开发了组合物和加工方法,以优化热处理的低合金钢的冲击韧性。 所公开的钢组合范围提供了一种轻微回火的马氏体组织,其中基本上不存在诸如钛和铝的晶粒细化沉淀物形成元素,并且通过施加适当的方式使得通过硬化操作保留的铁/合金碳化物的含量最小化 在大约900℃或更高的温度下进行奥氏体化的热处理,然后在约180℃淬火和轻微回火。