水火成形工艺温度对10CrNiCu钢显微组织和力学性能的影响

为了研究不同水火成形温度对10CrNiCu钢组织及性能的影响，在标准水火成形工艺评定试板上进行了不同温度水火成形试验，每种温度采用三次重复下火试验。工艺试验结果显示，10CrNiCu钢经历678~983 ℃水火成形后，显微组织仍为铁素体与珠光体双相组织；随着水火成形温度升高，晶粒逐渐长大，且铁素体呈双峰分布，珠光体出现偏析和定向分布；随着水火成形温度升高，10CrNiCu钢的抗拉强度有所升高，而屈服强度、冲击功和硬度略有下降；当水火成形温度高于856 ℃时，10CrNiCu钢的焰道边缘处吸收冲击功与硬度均有所下降，且焰道边缘处附近硬度低于母材，最大下降幅度为18HV10，但均满足相关规范要求。研究表明，980 ℃水火成形后10CrNiCu钢仍有良好的服役性能，可以根据现场变形量的需求，选择合适的水火成形温度。

Influence of Line Heating Process Temperature on Microstructure and Mechanical Properties of 10CrNiCu Steel

In order to study the effects of different line heating temperatures on the microstructure and properties of 10CrNiCu steel, line heating tests at different temperatures were carried out on the standard line heating process evaluation test plate. Three repeated annealing tests were carried out at each temperature. The process test results show that the microstructure of 10CrNiCu steel is still ferrite and pearlite after line heating at 678~983 ℃. With the increase of line heating temperature, the grain grows gradually, the ferrite is bimodal distribution, and the pearlite is segregation and directional distribution. With the increase of line heating temperature, the tensile strength of 10CrNiCu steel increases, while the yield strength, impact energy and hardness decrease slightly. When the line heating temperature is higher than 856 ℃, the absorbed impact energy and hardness at the edge of the flame path of 10CrNiCu steel decrease, and the hardness near the edge of the flame channel is lower than the base metal, with a maximum decrease of 18HV10, but all meet the requirements of relevant specifications. The research shows that 10CrNiCu steel still has good service performance after 980 ℃ line heating. The appropriate line heating temperature can be selected according to the demand of field deformation.