Abstract: The  structure  and  properties  of steel  with  three  kinds  heat  treatment  processes  -  quenched  at  880  ℃  for 30 min oil cooling + tempered at 600 ℃ for 60 min air cooling,normalized at 860 ℃ for 30 min air cooling and two-phase region  subcritical  treated  at  780  ℃  for  30  min  air  cooling,in  order  to  get  a  simplified  heat  treatment  process  of 40SiMnCrNiMo for rock drill tools. The results showed that the HV microhardness value at bainite region of subcritical heat treated steel lowed than that of normalized steel and V- notched impact energy was 30 J higher than that of normalized steel (12J)and  approached  to  that  of quenched  and  tempered  steel(40  J).  The  test  for  service  life  of rock  drill  tools  indicated  that as compared with average  10.78 m drill pace of advance of normalized steel tool,the average drill pace of advance of suberitical treated steel tools was  108.30 m to meet the requirement of use and to be available to replace quenched and tempered drill tools.

Key words: High Strength Steel 40SiMnCrNiMo, Rock Drill Tool, Suberitical Heat Treatment, Structure, Mechanical Properties

摘要： 为简化40SiMnCrNiMo钢钎具的热处理工艺,试验了880℃30min油冷+600℃60min空冷的调质处理,860℃30min空冷的正火和780℃30min空冷的两相区亚临界热处理后钢的组织和性能。结果表明,亚临界热处理后钢中贝氏体区HV显微硬度值低于正火钢,钢的V-型冲击功为30J,高于正火后钢V-型冲击功(12J),接近调质后的V-型冲击功(40J)。钎杆寿命试验得出,正火钢钎具平均钻孔进尺10.78m,亚临界热处理钢钎具平均钻孔进尺108.30m,可满足使用要求和替代调质处理钎杆。

关键词: 40 SiMnCrNiMo 高强度钢, 钎 具, 亚温热处理, 组 织, 机械性能