试题与答案

根据碳当量的高低，钢材焊接性能可分为哪三种？

来源：www.tikuol.com
题型：问答题 简答题

题目：

根据碳当量的高低，钢材焊接性能可分为哪三种？

答案：

参考答案：

（1）C当量＜0.4%，钢材塑性好，钢的淬硬和冷裂倾向不大，焊接性良好。

（2）C当量=0.4～0.6%，钢材塑性下降，淬硬倾向明显，焊接性较差。

（3）C当量＞0.6%，钢材塑性低，淬硬倾向强，焊接性很差。

考点：工程材料机械工程材料机械工程材料题库
试题推荐
题型：阅读理解

Along the seashore(海边)，the tall coconut(椰子)trees waved in he wind. The sand was white in the bright sun, and the ocean was dark blue. The houses in the town near the shore, were painted white. The boats had been pulled up on the shore. Usually they would all be in the water with hard-working fishermen. But today was a holiday, and everyone was  preparing for the celebration that was going to take place that evening.

In the distance, men could be seen climbing the coconut trees. They were singing as they worked. There were monkeys in the trees, too. The monkeys were jumping up and down and screaming angrily.The climbers just laughed at the monkeys and continued to pick the fruits.

小题1:What is this passage about?

A．It tells us a story of the monkeys.

B．It describes the scene on the seashore.

C．It talks about the life of the fishermen.

D．It is about how the people celebrated a holiday.小题2:The boats had been pulled up on the shore because_________.

A．it was a holiday

B．the weather was too hot

C．there was going to be a storm

D．it was not the season for fishing小题3:The men climbed the coconut trees to_________.

A．pick the coconuts

B．catch the monkeys

C．look at the ocean far away

D．see who could climb high and fast小题4:The word "screaming" in Paragraph Two probably means _______.

A．singing and working

B．jumping up and down

C．running here and there

D．shouting in a high voice小题5:The monkeys were angry because________.

A．the men were trying to catch them

B．the men wanted to drive them away

C．the men got the coconuts , which were their food

D．the men climbed higher and faster than they did
查看答案
微信公众账号搜索答案