【摘要】 采用粉末冶金气压烧结技术制备了粗晶粒WC-Co硬质合金。通过变量搜索方法安排整个试验,研究了合金含碳量、烧结工艺参数、合金钴含量、添加剂镍、球磨球料比、球磨时间6个因素对合金的硬度和冲击韧度的影响程度。结果表明,对合金硬度影响大小的因素依次为:Co含量、混合料球磨时间、合金碳含量、球磨球料比和烧结制度。在试验范围内要获得最大硬度,Co含量为9wt%、球磨26 h、添加W调低碳含量、球磨球料比3∶1、在1380℃烧结。对合金冲击韧度影响程度的大小因素依次为:烧结制度与Ni含量的交互作用、碳含量与烧结制度的交互作用、碳含量、Co含量与Ni含量的交互作用、Co含量。在试验范围内要获得最大的冲击韧度,需要在1345℃烧结、按Co∶Ni=9∶1添加Ni、采用饱和碳含量、Co含量11wt%。硬度和冲击韧度对合金含碳量、含钴量、烧结温度的要求是相反的。更多还原

【Abstract】 The coarse grain WC-Co cemented carbide was manufactured through powder metallurgy with the gas pressure sintering.Effects of some factors including carbon content,sintering parameters,cobalt content,nickel content and ball milling parameters on the hardness and impact toughness of the alloy were investigated by the Shainin’s variables search experiment design.The results show that the effective sequence from high to low on the hardness is cobalt content,ball milling time,carbon content,mass ratio of ball/powder and sintering parameters.In order to get the highest hardness of the alloy,some technology condition is needed,such as cobalt content 9wt%,ball milling time 26 h,suitable lower carbon content,mass ratio of ball/powder 3∶1 and sintered at 1380 ℃.However,the effective sequence from high to low on the impact toughness is interaction between sintering parameters and nickel content,interaction between carbon content and sintering parameters,carbon content itself,interaction between cobalt content and nickel content,cobalt content itself.In order to get the biggest impact toughness,it is needed that the alloy is sintered at 1345 ℃,and added nickel by ratio Co∶Ni=9∶1,contains saturated carbon content and 11wt% cobalt.Finally,it reveals that the technology requirement between the hardness and the impact toughness is opposited entirety in carbon content,cobalt content and sintering temperature.更多还原