The Short-term High Temperature Tensile Properties of 45CrNiMo1VA Ultra-high strength Steel

摘要

In this paper, we described the condition about the short-term tensile testing of 45CrNiMo1 VA steel at 650 °C;and combining with current knowledge about the short-term tensile properties of 45CrNiMo1 VA steel at high temperature, we also made a careful analysis of the testing results.The results of testing and analysis indicate that at 650 °C, the short-term tensile strength of 45CrNiMo1VA steel that was quenched and then tempered at 530 °C is relatively low, and its tensile strength and proof strength, plastic extension are about 20％ of those ones at ambient temperature;in addition, the short-term tensile strength of 45CrNiMol VA lowers with increasing testing temperature.The strength of the 45CrNiMol VA steel that was quenched and tempered at 500 °C ～550 °C declines by small margin with increasing testing temperature when testing temperature is under 500 °C;and the strength declines dramatically with increasing temperature, relevant to continued tempering transformation of material structure, when it is between 550 °C ～ 700 °C.When it is over 700 °C, the strength becomes very low and declines, again, by small margin with increasing temperature.The readings of the short-term tensile strength are also found relevance to the holding time of heated samples and times of heating.The longer the holding time, and the more times it is heated,the lower the strength reading is.