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φ0.6～1.0mm小钻头测试维氏硬度时,一般需将小钻头装上夹具或镶嵌后磨制。但这两种方法都有一定的不足之处。上夹具磨制时要用砂轮将夹具与小钻头同时磨去一定深度,需要花费一定的时间。再则,上夹具时不能将夹具螺丝拧得非常紧,因此加载荷时,小钻头常常发生松动,尽管这种松动很小,但却能改变压痕形状,影响了测量值的准确性。另外,小钻头并未直接与硬度计的载物台接触,而是靠夹具的支持,无疑对测量值都有影响。将小钻头镶嵌后磨制尽管方便,但小钻头并未直接与载物台接触,而是镶嵌在一定厚度(约15mm)的电木块中;由于电木块与载物台及小钻头硬度的差别较大,也会使硬度测量值存在一定的误差,并且镶嵌小钻头也要花费一定时间。采用胶粘法制备试样,将小钻头在砂纸上轻磨,除去铁皮和油污,并磨出一定宽度的平面后,用502胶
φ0.6 ~ 1.0mm small bit test Vickers hardness, the general need to install a small drill bit or mosaic after grinding. However, these two methods have some shortcomings. Grinding on the fixture with a small wheel to the fixture with a small bit while grinding to a certain depth, it will take some time. Furthermore, the fixture can not be tightened very tightly on the fixture, so the small bit often loosens when the load is applied. Although the looseness is small, the shape of the indentation can be changed, which affects the accuracy of the measured value. In addition, the small drill does not directly contact with the stage of the durometer, but by the support of the clamp, undoubtedly have an impact on the measured value. The small bit inlaid after grinding despite the convenience, but the small bit is not in direct contact with the stage, but inlaid in a certain thickness (about 15mm) bakelite block; as the bakelite and stage and small bit hardness The larger the difference, there will be some hardness measurement error, and inlaid small bit also takes some time. Using adhesive method to prepare the sample, the small drill on the sand light grinding, remove the metal and oil, and grinding out a certain width of the plane, 502 glue