Influence of various heat treatments on fatigue crack growth in 42CrMo4 steel under mixed modes I plus II and I plus III

The article addresses the results of the study of the examination of fatigue fracture in mixed and I + II and I + III modes in heat treated steel 42CrMo4. Three types of thermal treatments were performed, each caused various mechanical properties of the material. Tests were performed on two sample types: compact tension specimen (CTS) and rectangular cross-sectional samples for mixed mode and I + III. Mixed mode I + II tests were performed for 30 and 60 degrees load angles while the mixed mode test I + III was carried out for 30 and 45 degrees. In addition, the paper shows crack paths for all cases tested. Presented research aims to expand the knowledge of fatigue crack development under mixed mode while taking into consideration different mechanical properties of the same composition-wise material. The aforementioned knowledge is a significant contribution to defining the material fatigue under complex load, independently to sample geometry and number of other limitations.

Automated summary

The article discusses the results of a study on fatigue fracture in mixed and I + II and I + III modes in heat treated steel 42CrMo4. It presents different mechanical properties resulting from various thermal treatments and demonstrates tests conducted on different sample types and load angles. The research aims to enhance understanding of fatigue crack development under mixed modes and provide valuable insights into the material's behavior under complex loads.