焊后热处理（550～560℃）可以消除热应变时效，对低碳钢及某些合金结构钢的影响，恢复其韧性。
参考答案：对
(2014·枣庄模拟)—He should have been warned of the danger.
—________，but he wouldn’t listen to me.
A．So he had
B．So had he
C．So was he
D．So he was
在计算机系统中用来连接CPU、内存储器和I/O接口的总线称为系统总线。 (3) 总线属于系统总线技术的一种。
A．IEEE-1394
B．EISA
C．RS-232
D．USB
