日韩毛片免费无码无毒视频观看|久久无码人妻精品一区二区三区|欧美日韩一区二区三区免费观看|极品粉嫩嫩模大尺度无码视频

common problem

Under what conditions can spray welding be used?

author:admintime:2019-09-22 22:20click:
            Spray welding is to reheat the preheated self-soluble alloy powder coating to 1000-1300 C, melt the particles, float the slag onto the surface of the coating, and disperse the boride and silicide in the coating, so as to achieve good bonding between the particles and the surface of the substrate.
            Spray welding process is suitable for the following situations:
            1. Surface loads of various kinds of carbon and low alloy steels are large, especially those subjected to impact loads. For workpieces with bonding strength of 350-450N/mm2, spray welding hardness HRC150 < 65, coating thickness from 0.3 to several millimetres, and surface roughness of spray welding layer after grinding can reach Ra0.4-0.1 micrometres.
            2. When used in corrosive media, the coating is required to be compact and porous.
            3. Hardening, carburizing, nitriding and hard chromium plating are used in the original design of workpiece surface, which requires high hardness.
            4. Workpiece working environment is bad, such as strong abrasive wear, erosion wear, cavitation and so on.
            5. Oxygen-acetylene flame alloy powder spray welding process is suitable for surface strengthening or repairing of various carbon steel and low alloy steel parts, but some characteristics of parts material should be noticed. When the linear expansion coefficient of matrix material differs greatly from that of alloy spray welding layer, it should be used cautiously when the linear expansion coefficient of matrix material is less than 12 *10-6/~C and more than 12 *10-6/~C, so as to avoid manufacturing. Cracks can also be difficult to spray welding if the content of elements with high affinity to oxygen in matrix metals is more than 3%, the total content of elements such as tungsten and molybdenum is more than 0.5%, or the sulfur content in steel is more than 0.5%. This is because these materials are easy to form dense and stable oxide film by interaction with oxygen to prevent melting. The wetting effect of the alloy on the matrix will cause the liquid alloy to roll like a "sweat bead" during remelting. Therefore, the adaptability of the spray welding process to the sprayed matrix material should be paid attention to.
            6. Metal materials that can be sprayed without special treatment:
            7. Metal materials that need to be preheated at 250-375 C after spray welding need to be slowly cooled.
            8. Metal materials requiring isothermal annealing after spray welding

Telephone

0769-85415700

function

Price

quality

service

Wechat sweep

Mobile phone sweep

少妇人妻邻居| 亚洲va精品va国产va| 天天摸日日摸狠狠添| 国产在线aaa片一区二区99| 日韩av无码社区一区二区三区| 精品无码成人片一区二区98| 一边摸一边做爽的视频17国产 | 国产成人无码精品久久久露脸| 国产乱人伦在线播放| 国产黄大片在线观看| 亚洲不卡中文字幕无码| 国产白嫩护士被弄高潮| 丰满岳乱妇在线观看中字无码| 国产精品福利一区二区久久| 日产日韩亚洲欧美综合在线| 俺去啦最新官网| 亚洲人成人网站在线观看| 欧美人禽杂交狂配| 精品久久久久久综合日本| 国产男女猛烈无遮挡免费视频网站 | 久久精品女厕偷拍视频| 欧美深性狂猛ⅹxxx深喉| 亚洲一区二区精品自拍| 欧美激情一区二区三区成人| 国产综合AV一区二区三区无码| 欧洲女人牲交性开放视频 | 国产成人综合在线视频| 最近免费中文字幕| 无码国产精品一区二区高潮| 国产女人喷潮视频免费| av在线亚洲男人的天堂| 亚洲成AV人在线播放无码| 偷看农村妇女牲交| 欧美日韩精品久久免费| 人妻有码中文字幕| 国产人妻人伦精品1国产丝袜| 欧美牲交a欧美牲交aⅴ免费| 麻豆成人久久精品二区三区免费| 日本边添边摸边做边爱| 久久久久国精品产熟女久色| 免费观看交性大片|