摘要
通过热压烧结制备了以2%(质量分数)MgO–8%Lu_2O_3和2%MgO–8%Gd_2O_3为烧结助剂的2种Si_3N_4刀具(分别记作SN–L和SN–G)。以HT250为工件材料,对其切削性能进行了研究。结果表明:SN–G切削过程更稳定,刀具寿命更长,其有效切削长度约为2 600 m,是SN–L的2倍左右。两者后刀面磨损形貌没有明显差别,磨粒磨损和黏结磨损是主要的磨损机理。SN–G基体的晶粒较细小,增强晶粒的长径比较高,其抗弯强度和断裂韧性均比SN–L高10%左右,具有更高的晶界结合强度,在切削过程中不易发生晶粒脱落,因而刀具耐磨性更好,寿命更长。
Si3N4 cutting tools with 2%MgO-8%Lu2O3 and 2%MgO-8%Gd2O3 additives （i.e., SN-L and SN-G） were prepared via hot-pressing sintering, respectively. The cutting performance was investigated using HT250 cast iron as a work piece. The results show that SN-G has a better cutting performance with a higher stability during cutting process and a longer tool life, and the effective cutting length of SN-G is 2 600 m that is twice greater than that of SN-L. The morphology of the worn flank face of SN-L and SN-G has no significant difference, and the wear mechanisms mainly involve abrasive and adhesive wears. The size of matrix grains of SN-G is smaller, and the aspect ratio of reinforced grains is higher. The fracture strength and toughness of SN-G both are approximately 10% greater than those of SN-L. As a result, SN-G cutting tool has a higher wear resistance and a longer tool life.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2017年第6期836-840,共5页
Journal of The Chinese Ceramic Society
基金
广东省引进创新科研团队计划(2013G061)
国家自然科学基金(51402055)资助
关键词
氧化镁-氧化钆/氧化镥
氮化硅
切削
刀具寿命
磨损机理
magnesia-gadolinium oxide/lutetium oxide
silicon nitride
cutting
tool life
wear mechanism
