论文部分内容阅读
采用高压扭转法在440℃下将纯钨粉直接固结成致密体材料,并用金相显微镜、显微维氏硬度计、扫描电镜和X射线衍射仪分析高压扭转对纯钨粉致密固结、晶粒细化和室温脆性的影响。结果表明:高压扭转后钨粉颗粒间的孔隙得到有效闭合,颗粒结合界面无明显缝隙,界面结合较好;高压扭转钨坯的显微硬度HV为854~1 191,晶粒尺寸为141~394nm,室温显微硬度压痕规整,边界清晰,压痕四角无裂纹。与粉末压制烧结工艺相比,高压扭转工艺更能有效消除钨颗粒团聚,减少孔隙数量,细化晶粒尺寸,改善基体组织均匀性和室温脆性。
The pure tungsten powder was directly solidified into a dense material by high pressure torsion method at 440 ° C. The dense tungsten powder was solidified by high pressure torsion with a metallographic microscope, a micro Vickers hardness tester, a scanning electron microscope and an X-ray diffractometer. Grain refinement and room temperature brittleness. The results show that the pores between the tungsten powder particles are effectively closed after the high-pressure torsion, the grain-bound interface has no obvious gap and the interface is well bonded. The HV hardness of high-pressure twisted tungsten billet is 854-1191 and the grain size is 141-394nm , Room temperature micro-hardness indentation regular, clear boundary, indentation corners no crack. Compared with the powder compacting and sintering process, the high-pressure torsion process can effectively eliminate the agglomeration of tungsten particles, reduce the number of pores, refine the grain size, and improve the matrix homogeneity and room-temperature brittleness.