烧结温度对不含氮原料制备的脱β层梯度硬质合金的影响  

Effect of Sintering Temperature on Graded Cemented Carbides with Beta Free Layer Prepared with Nitrogen Free Raw Material

作　　者：史留勇[1] 黄继华[2] 林彬[3] 王娟[1] 罗洪峰[1] 陈致水[1] 

机构地区：[1]海南大学机电工程学院,海南海口570228 [2]北京科技大学材料科学与工程学院,北京100083 [3]天津大学机械工程学院,天津300072

出　　处：《稀有金属与硬质合金》2015年第3期50-53,62,共5页Rare Metals and Cemented Carbides

基　　金：国家自然科学基金(51404084);海南省自然科学基金(513137);海南大学科研启动金(kyqd1313);天津大学自主创新基金

摘　　要：采用不含氮硬质合金原料,通过在梯度烧结工艺之前添加一步微压氮化烧结工艺制备脱β层梯度硬质合金;采用SEM观察合金表层的组织结构,图像分析工具测量脱β层的厚度。结果表明:在添加微压(氮气分压为0.5kPa)氮化烧结工艺的情况下,编号Co-8梯度硬质合金在1 420、1 450、1 480℃,1h的烧结工艺下形成脱β层的厚度分别为8、13、24μm;而编号Co-6梯度硬质合金在1 420℃时所形成的脱β层的厚度接近于零,在其他两种烧结温度下,所形成的脱β层的厚度也明显低于编号Co-8梯度硬质合金。与添加Ti(C,N)的原料相比,在相同的烧结工艺下,本文所采用的不含氮原料制备梯度硬质合金的脱β层厚度也明显降低。Graded cemented carbide with beta free layer was fabricated with nitrogen free raw material by adding a sintering step of micro-pressure nitriding before gradient sintering.The microstructure of the surface layer of the graded cemented carbide was investigated by SEM and the depth of beta free layer was measured by an image analysis tool.The results show that with the added micro-pressure nitriding(0.5kPa N2 partial pressure),the graded cemented carbide No.Co-8sintered at 1 420℃,1 450℃and 1 480℃for 1hhas beta free layer depths of 8μm,13μm and 24μm,respectively.However,the beta free layer depth is close to zero of the graded cemented carbide No.Co-6sintered at 1 420 ℃,and its beta free layer depths are also significantly less than those of No.Co-8sintered at the other two sintering temperature.With the same sintering process,the beta free layer depth of the graded cemented carbide prepared with nitrogen free raw material is obviously lower than that with Ti(C,N)-containing raw material.

关 键 词：梯度硬质合金 脱β层 微压氮化 烧结温度 不含氮原料 影响 

分 类 号：TG135.5[一般工业技术—材料科学与工程]