还原气氛热压烧结技术及其节能减排效益的研究

采用还原气氛带压的钟罩炉烧结(以下简称还原热压烧结)和传统热压烧结两种方式制备金属结合剂试样条和金刚石节块,利用X射线衍射(XRD)、扫描电镜(SEM)、硬度计、电子万能试验机、磨耗比测定仪和氮/氧分析仪等手段,研究两种烧结技术制备的金属结合剂试样条和金刚石节块的微观组织与宏观性能。结果表明,利用两种不同的烧结方式制备的金属结合剂试样条在微观上表现物相结构相同,低熔点Cu-Zn合金组份没与高熔点Fe-Ni合金组份产生冶金结合;在宏观上还原热压烧结制备的金属结合剂试样条的硬度略低于传统热压烧结的,而其抗弯强度和耐磨性均较优。与传统热压烧结工艺相比,还原热压烧结技术在低温低压下既可提高结合剂对金刚石的把持力,又可降低金刚石的热腐蚀。此外,利用还原热压烧结技术能大大降低成本和减少废气的排放。在实际产品应用中,利用还原热压烧结技术制备的φ350 mm金刚石锯片深受国内外客户的好评。

Study on hot pressed sintering under reducing condition and its benefit from energy saving and emission reduction

Metal bond matrix samples and diamond segments were respectively prepared by reducing-hot pressing sintering and traditional hot pressed sintering. Their microstructure and macro properties were investigated by X-ray diffractometry （XRD）, scanning electron microscope （SEM）, hardness analyzer, nitrogen/oxygen content analyzer, abrasion ratio testing, etc. The results showed that metal bond matrix samples prepared by two different sinterings had the same phase structure, and a metallurgical bonding was not formed between the low-melting-point Cu-Zn alloy and high-mehing-point Fe-Ni alloy. From a macro point, the hardness of metal bond matrix samples prepared by reducing-hot pressing sintering was lower than that prepared by traditional hot pressed sintering, but its bending strength and wear resistance were better. Compared with diamond segments prepared by traditional hot pressed sintering, the holding force of the matrix to diamonds was improved and the thermal deterioration of diamond was reduced under low temperature and low pressure by using reducing-hot pressing sintering technology. Meanwhile, the cost of production and the exhaust emission were decreased by reducing-hot pressing sintering. Our φ350 mm diamond saw blades made by reducing-hot pressing sintering were high-evaluated by foreign and domestic customers.