电阻加热对微合金钢组织性能影响的研究

RESEARCH OF THE RESISTANCE HEATING EFFECTS ON PROPERTIES AND MICROSTRUCTURES OF MICROALLOYED STEELS

利用电阻加热设备对160 mm×15 mm×3 mm矩形试样进行加热后局部喷水冷却,研究试样不同位置的温度变化情况以及不同位置冷却后的组织性能变化。通过腐蚀原始奥氏体晶粒研究加热时间和电流密度对晶粒的影响。结果表明:采用电阻加热,试样温度场呈现"中间高,两边低"的分布规律,中间存在一定长度的均温区。电流密度一定时,最高加热温度也是一定的,且该温度随着电流密度的增加而增加。加热时间越长,电流密度越大,原始奥氏体晶粒越大。

In order to study the specimen temperature variations at different locations and changes of the properties and microstructures after cooling, a 160 mm× 15 mm × 3 mm rectangular specimen was heated by the resistance heating equipments and then cooled by water. The influences of the heating time and current density on the grains were studied by corroding austenite grains. The results showed that after resistance heating, the temperature field was distributed as ＂ high in the middle, low on both sides＂ and there was a certain length uniform temperature zone. When current density was certain, the heating temperature was constant, and the temperature increased with increasing of current density. When heating time longer, the current density greater and the original austenite grain bigger.