Effects of Various Errors on the Superficial Rockwell Hardness Reading : 1st Report, Tests Using the Steel Ball Indenter

概要

論文の詳細を見る
The superficial Rockwell hardness tester comes into use for quality control of thin metal sheets because of quickness of testing. Therefore the establishment of JIS (Japanese Industrial Standard) on this hardness tester is urgently needed. This report makes clear the effects of errors in the preliminary load W_1 kg, the total load W_2 kg and the diameter D mm of the steel ball indenter on the superficial Rockwell hardness reading. The extended Meyer's law that has been successfully used for the Rockwell hardness test is again applied to this test although the loads in the latter are smaller than in the former. The deviation of the hardness reading is theoretically analyzed and the following formula is obtained, taking the Meyer's index n as 2.3. For example, ΔH_R30T=(100-H_R30T)(0.044 9ΔW_1-0.033 7ΔW_2+0.466ΔD). A good agreement is observed between the calculated values and the experimental ones. In addition, the authors' proposal for establishing a tentative JIS is shown.
一般社団法人日本機械学会の論文