Aluminum nitride （AIN） precipitates and microstructure of 4 wt.% （Si＋AI） non-oriented electrical steel were investigated. The 2.0 mm thick cast strips with three different silicon/aluminum （Si/AI） ratios were p...Aluminum nitride （AIN） precipitates and microstructure of 4 wt.% （Si＋AI） non-oriented electrical steel were investigated. The 2.0 mm thick cast strips with three different silicon/aluminum （Si/AI） ratios were produced by twin-roll casting process, then the strips were reheated, warm rolled, cold rolled and annealed. The microstructure and AIN precipitates were characterized using optical microscopy, scanning electron microscopy and transmission electron microscopy. The results showed that with the increase of Si/AI ratio, on the one hand, the casting microstructure changed from columnar grains to equiaxed grains, and the uniformity of annealed microstructure was improved; On the other hand, the number of AIN precipitates in cast strips reduced meanwhile the distribution became dispersed. By the reheat treatment, the size and distribution of the AIN precipitates can be changed. Moreover, the grain size of the annealed strips is in the range of 20-50 #m, at the same time, many AIN precipitates were located at grain boundaries. Therefore, controlling the Si/AI ratio is a simple method to obtain desired microstructure. Then AIN precipitates in non-oriented electrical steel prepared by twin-roll casting process hinder markedly the recrystallized grains growth, A compatible reheat treatment can be an approach worth exploring to control the behavior of AIN precipitates.展开更多
Combining with the study of analogue experiments and test analysis, the kinetics of precipitation and growth of AlN and MnS in non-oriented electrical steel produced by the CSP process is calculated. The results show ...Combining with the study of analogue experiments and test analysis, the kinetics of precipitation and growth of AlN and MnS in non-oriented electrical steel produced by the CSP process is calculated. The results show that the precipitate phase particles of AlN and MnS in typical non-oriented electrical steel grades produced by the CSP process have grown to some extent in the soaking stage, but the precipitation contents are less than 20% of the total contents of nitride and sulfide. The precipitate phase particles of AlN and MnS have precipitated almost after the hot rolling process. The precipitation contents are more than 80% of the total contents of nitride and sulfide, but it is very late for the precipitate phase particles to grow at the end of the hot rolling process.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.50734001 and 51004035)
文摘Aluminum nitride （AIN） precipitates and microstructure of 4 wt.% （Si＋AI） non-oriented electrical steel were investigated. The 2.0 mm thick cast strips with three different silicon/aluminum （Si/AI） ratios were produced by twin-roll casting process, then the strips were reheated, warm rolled, cold rolled and annealed. The microstructure and AIN precipitates were characterized using optical microscopy, scanning electron microscopy and transmission electron microscopy. The results showed that with the increase of Si/AI ratio, on the one hand, the casting microstructure changed from columnar grains to equiaxed grains, and the uniformity of annealed microstructure was improved; On the other hand, the number of AIN precipitates in cast strips reduced meanwhile the distribution became dispersed. By the reheat treatment, the size and distribution of the AIN precipitates can be changed. Moreover, the grain size of the annealed strips is in the range of 20-50 #m, at the same time, many AIN precipitates were located at grain boundaries. Therefore, controlling the Si/AI ratio is a simple method to obtain desired microstructure. Then AIN precipitates in non-oriented electrical steel prepared by twin-roll casting process hinder markedly the recrystallized grains growth, A compatible reheat treatment can be an approach worth exploring to control the behavior of AIN precipitates.
基金Mega-Projects of Science Research for the 10th Five-Year Plan (2004BA318B)
文摘Combining with the study of analogue experiments and test analysis, the kinetics of precipitation and growth of AlN and MnS in non-oriented electrical steel produced by the CSP process is calculated. The results show that the precipitate phase particles of AlN and MnS in typical non-oriented electrical steel grades produced by the CSP process have grown to some extent in the soaking stage, but the precipitation contents are less than 20% of the total contents of nitride and sulfide. The precipitate phase particles of AlN and MnS have precipitated almost after the hot rolling process. The precipitation contents are more than 80% of the total contents of nitride and sulfide, but it is very late for the precipitate phase particles to grow at the end of the hot rolling process.
