聚晶金刚石复合片聚晶层的冲击破坏研究

Study on Impact Failure of Polycrystalline Layer in Polycrystalline Diamond Compact

提出了一种倾斜冲击破坏实验方法,能够实现对聚晶金刚石复合片(PDC)聚晶层的冲击破坏试验。采用数显工具显微镜和扫描电子显微镜对PDC聚晶层冲击破坏断口进行观测,结果表明,新的实验方法使PDC处于近刚性接触的环境下,实现对PDC聚晶层点-面的冲击破坏,能够评价聚晶层抗冲击破坏能力的大小;在冲击破坏过程中,聚晶层冲击点边缘部分形成多条形变带,沿形变带破坏产生裂纹并长大而形成断裂面。并对PDC聚晶层冲击破坏的机理进行了讨论。

An inclined impact failure method was proposed, by which impact failure test of the polycrystalline layer in polycrystalline diamond compact （PDC） could be realized. The impact fractures in the polyerystalline layer were investigated by means of digital tool microscope and scanning electronic microscope. The results indicated that the new method made the contact state of PDC approximately rigid, realizing point-to-face impact failure of the polycrystalline layer. The resistance ability of the polycrystalline layer to the impact failure could be evaluated by this method. During the course of impact failure, many deformation bands formed around the impact point on the polycrystalline layer. Along the deformation bands cracks developed and formed fracture surfaces. The impact failure mechanism of the polycrystalline layer in PDC was discussed.