no blemish

The improvement for surface non-defect rate of HP295 continuous casting billet;

HP295连铸坯表面无缺陷率的提高

In the paper, preparation of“defect-free”α-Si_3N_4 whiskers is made by ultrafine Si_3N_4 powder ofhigh activity and high purity.

用这种超细粉在一定温度范围内原位生长出“无缺陷”的α－Ｓｉ＿３Ｎ＿４晶须，其截面直径×长的尺寸分别为（０。