聚晶金刚石复合片脱钴试验的抗弯强度对比分析

Comparative Study on Bending Strength of PDC Composite Layer

对不脱钴和脱钴的聚晶金刚石复合片(PDC)复合层分别进行抗弯强度测试,并根据其原理计算抗弯强度。采用XRD和SEM对断裂面的物相和形貌进行分析,观察钴含量对抗弯强度的影响。结果表明:脱钴后,PDC金刚石层中Co含量降低,韧性变差,受到载荷作用时首先出现裂纹,导致复合层在完全断裂前载荷-位移曲线有略微下降的趋势;两个系列PDC样品的复合层抗弯强度均较未脱钴的有明显降低,说明Co相的存在有助于提高PDC的抗弯强度;且随着脱钴深度的增加,PDC复合层抗弯强度的降幅增大。

The composite layer of polycrystalline diamond compact(PDC)and cobalt-removed of PDC was subjected to the three-point bending strength test,and the bending strength was calculated according to the principle.XRD was used to analyze the phase compositions of the fracture surface of PDC,and SEM was used to observe the morphology as well as the influence of Co content on the bending strength.The results show that due to the decrease of Co content in diamond layer of PDC after removing the cobalt,toughness of the diamond becomes poorer.Therefore,when the load is affected,the first crack appears in the diamond layer,resulting in a slight downward trend of the load-displacement curve before it is completely broken.The bending strength of the two series samples of PDC after removing the cobalt is obviously lower than that of PDC products.And the increase of the leaching depth of PDC will lead to a greater reduction of the bending strength.