钢铁材料的表面形变强化与疲劳强度

Surface Deformation Strengthening and Fatigue Strength of Ferrous Alloy

主要介绍常用合金结构钢、渗碳钢、低合金高强度钢及球墨铸铁等材料经整体热处理或表面化学热处理后再复合表而形变强化的综合应用(即复合强化),有针对性地研究了强化规律与疲劳强度的相互关系。研究指出,复合强化是发挥材料疲劳强度潜力的有效途径,可使高强度钢的σ_(-1n)/σ_b仍保持线性关系。提出了采用局部形变强化,克服零件的薄弱环节,使零件各部位的材料疲劳强度接近等强度设计的技术观点。并以断裂力学与表面微观组织结构的变化以及残余压应力等因素的有益作用探讨了强化机制,同时将研究结果有效地应用于生产。

Presented here is the comprehensive application of bulk heat treatment or surface chemical heat treatment and subsequent composite surface deformation strengthening (composite strengthening), of constructional alloy steel, carbonized steel, low alloyed high strength steel and nodular cast iron. The relationship between its strengthening law and fatigue strength is also objectively studied. Resulto of testing have shown, 1). Composite strengthing is an effective way to fully bring out potentialities of fatigue strength of materials. 2). The σ_(-1n)/σ_b ratio of high strength steel can be held in linear relationship. 3). It is suggested that, by partial deformation strengtheng, the weak points can be overcome, an iso-strength situation can be reached. Furthermore, from the viewpoint of fracture mechanics, the change of surface microstructure and residual compressive stress, several strengthening mechanism are studied. Meanwhile research results are applied effectively to actual production.