Steel is an interstitial solid solution with impurity carbon atoms in iron crystal lattice. A.正确B.错误 正确答案：正确

When stacked together, the unit cells form the whole crystal. A.正确B.错误 正确答案：正确

The advantages of Hot-work operation are（） A.a increase in strengthB.successively repeatC.large deformationD.requiring more deformation energy 正确答案：successively repeat；large deformation

Protection methods against the metal corrosion include（） A.shielding the materialB.establishing the chemical makeupC.allowing the corrosive activity to continueD.setting a nonstructural parts to concentrate the corrosive activity 正确答案：shielding the material；establishing the chemi … 阅读详情>> "Protection methods against the metal corrosion include（）"

Possible alternations in the HAZ include the following（） A.recrystallization and grain growthB.forming the residual stressesC.steel may have been heated to temperatures sufficiently high so as to form marteniteD.stainless steel may be “sensitized” during welding 正确答案：recrystalliz … 阅读详情>> "Possible alternations in the HAZ include the following（）"

Typical lattices of most metals are（） A.Body-Centered CubicB.OrthorhombicC.Hexagonal Close-PackedD.Face-Centered Cubic 正确答案：Body-Centered Cubic；Hexagonal Close-Packed；Face-Centered Cubic

Based on their dimensionality, defects are classified into（）,（）and（）. A.point defectsB.line defectsC.space defectD.area defects 正确答案：point defects；line defects；area defects

From this diagram, a lot of information can　be got such as（） A.yield pointB.ultimate strengthC.fracture　pointtensile strengthD.fracture　point 正确答案：yield point；ultimate strength；fracture　point

Phase diagram is the graphical representation of a material system under varying conditions of（） A.temperatureB.structureC.compositionD.processing 正确答案：temperature；composition

The most common cast iron types are（） A.gray cast ironB.nodular cast ironC.white cast ironD.malleable cast iron 正确答案：gray cast iron；nodular cast iron；white cast iron；malleable cast iron

（）is an alloy of Cu-Zn. A.brassB.copperC.bronzeD.aluminum 正确答案：brass

The predominant alloying element of the stainless steel is（） A.manganeseB.chromiumC.carbonD.nickel 正确答案：chromium