问题:亚共析钢冷却到PSK线时,发生共析转变,奥氏体转变成()A、珠光体B、铁素体C、珠光体+铁素体...
Friday, September 15, 2023
Sunday, September 11, 2022
Sunday, September 11, 2022
问题:退化加热过程中炉台气氛实际温度较设定温度允许波动()℃...
Sunday, September 11, 2022
问题:在选用电热元件材料时,必须考虑炉子的形状和工作状态,以免造成烧坏...
Sunday, September 11, 2022
问题:冷退火酸洗线采用打孔用于焊缝跟踪,其打孔直径为()mm。...
Monday, September 12, 2022
问题:在选用电热元件材料时,必须考虑炉子的形状和工作状态,以免造成烧坏...
Sunday, September 11, 2022
Sunday, September 11, 2022
问题:金属及合金在一定过冷度或过热度条件下,自等温保持开始到开始发生相变所经历的时间叫做孕育期。()...
Friday, September 13, 2024
问题:有甲、乙两个工件,甲工件硬度是230HBS,乙工件的硬度是HRC...
Sunday, September 11, 2022
Thursday, March 13, 2025
问题:金属塑性一般受金属晶粒影响,晶粒大,塑性差。()...
Wednesday, October 25, 2023
Sunday, September 11, 2022
Sunday, September 11, 2022
Sunday, September 11, 2022
Monday, September 12, 2022
问题:作布氏硬度试验时,当试验条件相同时,其压痕直径越小,材料的硬度越...
Sunday, September 11, 2022
问题:钢回火后韧性降低,可以用回火后()的方法加以避免。...
Friday, September 13, 2024
问题:退火炉操作工点炉前,必须检查所有()、阀门是否严密可靠。...
Thursday, March 28, 2024
Monday, June 23, 2025