【摘要】 为了研究低温对超高强度钢断裂行为的影响,采用37SiMnCrNiMoV钢的表面予裂板状试件,经正常热处理（930℃,15分,油淬,280℃回火）后,在-196～20℃的温度范围内进行试验。随温度的变化,其断裂韧度值由85kgf·mm^3/2（-196℃）变到195·7kgf·mm^<sub>3/2（20℃）,而试样平断口区域中准解理刻面的百分数由100％（-196℃）变到15％（20℃）。本文指出了超高强度钢与低碳钢冷脆行为的差异并进行了讨论。本工作中还研究了奥氏体化保温时间,含碳量和低温回火脆性对超高强度钢低温断裂行为的影响。更多还原

【Abstract】 In order to investigate the effect of low temperatures on the fracture behaviour of ultra high-strength steels, surface-cracked plate specimens of 37SiMnCrMoV steel （oil quenched and tempered at 280℃）were adopted.Fracture tests were arranged within the range of temperatures from -196℃ to 20℃.With variation of the temperature. The fracture toughness values varied frcm 85 kgf/mm^3/2 （at-196℃）to 195.7kgf/mm^3/2 （at 20℃）,and the percentage of quasi-cleavage area below the crack in the central flat fracture surface varied from 100%（at-196℃）to 15%（at 20℃）.The differences between the low-temperature brittleness behaviour of ultra highstrength steels and that of mild steels were compared and discussed.The influences of the holding time during austenization, the carbon content and the temper embrittlement on the fracture behaviour of ultra high-strength steels at low temperatures were investigated in this paper too.更多还原