摘要
本文以20CrMnMo 钢为对象比较全面地研究了不同渗碳层厚度、渗碳层碳含量以及不同心部组织对扭转流变硬化行为和断裂特征的影响。结果表明,渗碳件的屈服强度和流变硬化行为主要取决于心部组织。在心部组织相同的条件下,渗碳层的成分、组织和渗层厚度主要影响渗碳件的断裂应变,从而影响其断裂韧度。此外,在材质相同、强度水平相近的条件下,渗碳件的接触疲劳寿命随渗层厚度增加而增大的现象,从力学性能角度看是由于断裂应变随渗层厚度增加而增大,使断裂韧度增大所致,其原因与残余压力大小分布随渗层厚度变化有关。
The effect of carburized depth,carbon content and core structure on thetorsional flow harden behaviour and the fracture feature of 20CrMnM_ocarbuizing steel wasinvestigated in a relatively allround way.The results show that the core structure is themain factor which can influence the yield strength and the flow harden behavior of carbur-ing steels.When the core structures of carbuizing steels are the same,the fracture strain ofcarburized parts will mainly be affected by the carbon content,structure and depth of thecarburized layer,thus its toughness will be afffected by these factors also.In case the qualityand the strength level of carburizing steels are alike the improvement of contact fatigue lifeis associated with the increase of carburized depth,due to the fracture strain increases withthe increase of the carburized depth.
基金
国家自然科学基金
5860267
关键词
钢
渗碳
形变
断裂
渗层
疲劳
torsion property
deformation hardening
contact fatigue
carburizing steel structure
