2024知到网课 WELDABILITY OF METALS AND ALLOYS金属焊接性智慧树答案

第一章 单元测试

1、单选题：With carbon equivalent ( ), the steel has a low tendency to harden and cold cracking?
A:less than 0.50%
B:less than 0.80%
C:less than 0.60%
D:less than 0.40%
正确答案:【less than 0.40%】

2、单选题：( ) is not a factor that affects weldability.
A:operation skill
B:chemical composition
C:joint type
D:Welding process
正确答案:【operation skill】

3、多选题：The calculation formula of carbon equivalent of the IWS considers the influence of () on weldability.
A:chemical composition
B:diffusion hydrogen
C:welding process
D:welding structure&nbsp
正确答案:【diffusion hydrogen;welding process;welding structure&nbsp】

4、单选题：Maximum crack distance has been used to allow more accurate determination of the cracking ( ) range.
A:strength
B:toughness
C:size
D:temperature
正确答案:【temperature】

5、多选题：Weldability is not easily quantified, and can depend on a variety of factors, including  ( ).
A:operator and welder
B:physical specifics of the joint
C:welded structure
D:welding method
正确答案:【physical specifics of the joint;welded structure;welding method】

第二章 单元测试

1、单选题：The weldability of high-carbon steel is worse than that of low-carbon steel because high-carbon steel is with ( ).
A:higher carbon content
B:lower melting point
C:higher sulphur content
D:higher toughness
正确答案:【higher carbon content】

2、单选题：Normally, because of auto-tempering, the postweld microstructure of QTLA steel is ( ).
A:high carbon martensite
B:tempered martensite
C:ledeburite
D:upper bainite
正确答案:【tempered martensite】

3、多选题：QTLA steel is not susceptible to solidification cracking because it is with ( ).
A:low impurity content
B:low carbon content
C:low manganese content
D:low nickel content
正确答案:【low impurity content;low carbon content】

4、多选题：For HTLA steels, chromium is able to ( ).
A:decrease toughness of HTLA steels
B:increase toughness of HTLA steels
C:increase hardeness of HTLA steels
D:decrease hardeness of HTLA steels
正确答案:【decrease toughness of HTLA steels;increase hardeness of HTLA steels】

5、判断题：When you weld HTLA steels, you’d better to take advantage of auto-tempering.
A:对
B:错
正确答案:【错】

6、多选题：Auto-tempering occurs after welding when ( ).
A:peak temperature is high
B:Ms is high
C:carbon content of weld is low
D:cooling rate is slow
正确答案:【carbon content of weld is low;cooling rate is slow】

7、判断题：Before designing welding procedure, we’d better to analyze the weldability of the workpiece.
A:对
B:错
正确答案:【对】

8、判断题：To remedy the underbead cracking, we need to reduce cooling rate when we weld oil engine connecting rod.
A:错
B:对
正确答案:【对】

9、单选题：If the carbon content of a type of steel is 0.1%, this steel is a kind of ( ).
A:medium-carbon steel
B:HTLA steel
C:high-carbon steel
D:low-carbon steel
正确答案:【low-carbon steel】

第三章 单元测试

1、判断题：Weld metal of austenitic stainless steels is susceptible to weld decay.
A:对
B:错
正确答案:【错】

2、判断题：PWHT would be helpful to prevent the formation of weld decay in austenitic stainless steels.
A:对
B:错
正确答案:【对】

3、判断题：Adjusting welding sequence might be helpful to prevent the formation of knife-line attack in austenitic stainless steels.
A:错
B:对
正确答案:【对】