2007 年 115 巻 1345 号 p. 562-566
According to XRD analysis, when sprayed amosite was heated at over 900°C for 3 h, amosite crystal was not detected in the sample. In contrast, a part of the needlelike amosite grains were not detected in the sprayed amosite using a phase-contrast microscope analysis after heating at 500°C for 3 h. Then the color of the needlelike amosite grains changed to red, because Fe2O3 (hematite) was precipitated at the surface of the amosite grains. The grindability of the needlelike amosite grains was improved with an increase of the heating temperature. When the sprayed amosite was heated at 1100°C for 3 h, a fine powder with under aspect ratio of 3 was obtained after grinding.