关键词：cbn contents hardness phase composition 

摘要：Well-sintered polycrystalline cubic boron nitride(PCBN)composites with different contents of cubic boron nitride(CBN) were obtained using Al and TiN as additives under pressure of 5.5 GPa and temperature of 1450 ℃.The network structure of CBN grains and bonding materials was observed using scanning electron microscope(SEM).With the help of X-ray diffraction(XRD) analysis,TiB2 and AlN could be determined as main products and Al3 Ti also was detected in the Al-rich samples after sintering process.Furthermore,it was shown that Vickers hardness of composites was improved with the increase of CBN contents.However,the lifetime of PCBN composites was in negative correlation with the amount of CBN in turning GCr15 hardened steels,and the surface roughness of workpieces machined by these PCBN composites also showed the same trend.A series of cutting data confirmed that the low CBN content in PCBN composites could enhance the working durability and improve the surface quality in turning hardened steels.The present experiments also indicated that the lowest value of flank wear was not constant for different PCBN composites when they were used to machine several workpieces with different hardness.

金刚石与磨料磨具工程杂志要求:

{1}引用资料非来自原始出处时，应注明“转引自”。转引文献时，应先注明原始作品 之相关信息，再注明转引所据之文献。

{2}根据著作权法的有关规定，编辑部对来稿有权做文字性和技术性的修改、删减。如有特殊情况请在稿件附言中注明。

{3}每篇论文应有200字左右的“摘要”，3-8个“关键词”。摘要要求表达简练，语义确切，结构严谨；应包括目的、方法、结果和结论；用第三人称编写；应反映论文的主要内容。

{4}作者姓名、性别、出生年、籍贯、民族、工作单位、职称、学历、研究方向。

{5}基金论文所涉及的课题如取得国家或部、省级以上基金项目，应脚注于文题页左下方，作者单位上方，并附基金证书复印件，本刊将优先处理与刊登。

注：因版权方要求，不能公开全文，如需全文，请咨询杂志社