超声冲击对304不锈钢堆焊层组织及性能的影响-材料工程专业毕业论文.docx

超声冲击对304不锈钢堆焊层组织及性能的影响
Impact on Micro—structure and Properties of Type 304 Stainless Steel Surfacing Layer by URrasonic Impact Treatment
Abstract
The surface state of the material is usually the key factors which affect the service l舵, and poor performance or the presence of defects of the material surface will cause many ponents of early retirement,SO material surface strengthening technology IS
more and more power equipment all the year round in high pressure,high temperature,radiation and other harsh conditions without intermission operation,to ensure that nuclear power equipment safety of causative long life,there are more stringent
requirements on the material surface wear-resisting,corrosion resistance,antl tatigue
in tlle舶ld of nuclear power,the surface strengthening technology IS referred
to all extremely important is the monly used surface strengthening method in the manufacturing process of nuclear power , the surfacing layer iS welded structure。its microstructure and properties are e】【tremely uneven,
especially it Can not be avoid the residual tensile stress greatly in the surfacing layer that
affect the quality of the welding parts and the service life of nuclear power to
apply tive means to improve the surfacing layer surface structure,maprove the surlace properties of the material,prolong the nuclear power equipment safety causative lile IS always all important subject in the field of nuclear technology research.
Ultrasonic a new type of surface plastic deformation strengthening technology,
has e widely used to improve the weld microstructure,eliminating welding stress and effective the application of ultrasonic impact technology to the microstructure and
properties of the surfacing layer has almost rio this study,304 surfacing layer that iS the most COlTlnlonly used ha nuclear power equip’ment 1S research object,ultrasomc i