【摘要】 以廉价的Si、Mn、Cr、B为主要合金元素,加入少量Ti、N、Ca和稀土等元素细化和净化钢的组织,开发了不含钼、镍等贵合金的贝氏体钢,并研究了回火温度对钢的组织和性能的影响。研究发现铸钢经920℃空淬后,获得了细小的贝氏体组织。随着温度升高,钢的韧性不断增加,在450～500℃左右出现回火脆性,韧性下降。以后韧性随回火温度升高而继续提高。硬度随回火温度升高而下降,在300℃以下回火,硬度下降平缓,维持在HRC55以上。随着回火温度升高,销盘磨损条件下的耐磨性不断下降,而冲击磨损条件下则在300℃回火时具有优异的耐磨性。无钼镍空淬贝氏体铸钢用作球磨机衬板、破碎机锤头和挖掘机斗齿等备件材料,寿命比高锰钢提高100%～300%。更多还原

【Abstract】 Air-hardening bainitic cast steel free from molybdenum and nickel was successfully developed whose main alloy elements were silicon,manganese,chromium and boron.Moreover,there were a few titanium,nitrogen,calcium and rare earth elements in the cast steel that could refine and purify the structure of steel.The effect of temper temperature on the structure and property of cast steel was also studied.The results show that the microstructure of the cast steel quenched at 920 ℃ and cooled by air is fine bainite.The toughness of cast steel increases when the temper temperature increase.The temper brittleness appears and the toughness decreases while tempering at 450 ℃.Since then,the toughness increases continuously while increasing the temper temperature.The hardness decreases along with the increase of temper temperature.The decrease of hardness is slow and it exceeds HRC55 when the temperature is lower than 300 ℃.The wear resistance decreases along with the increase of temper temperature under the condition of two-body pin-on-disc wear.In the condition of impact wear,cast steel tempering at 300 ℃ has excellent wear resistance.The liner,hammer and bucket tooth made of air-hardening bainitic cast steel free from molybdenum and nickel have good service effect,whose life-span is higher than that of high manganese steel by 100%~300%.更多还原