密臀av,大胆亚洲成人社区,美国成人超碰在线播放,日韩操熟妇

Welcome to Dongguan Ningzhi Powder Metallurgy Co., Ltd. Official Website!
News
Industry News
Your current location:News >> Industry News >> View Contents
History of Powder Metallurgy
Time:2017/9/15 10:33:54  Views:

Powder metallurgy products are forming and sintering process of metal powder (or metal powder and non-metallic powder mixture) made of materials and products of the technology. It is a branch of metallurgy and materials science.

Powder metallurgy products from a wide range of applications, from general machinery manufacturing to precision instruments; from hardware to large machinery; from the electronics industry to the motor manufacturing; from the civilian industry to the military industry; from the general technology to cutting-edge high-tech, can see Powder metallurgy process of the figure.

Powder metallurgy development history:

Powder metallurgy method originated in three thousand years BC. The first method of making iron is essentially a powder metallurgy method.


The development of modern powder metallurgy technology has three important signs:

1, to overcome the refractory metal casting process of the difficulties. 1903 manufacturing tungsten wire, to promote the development of powder metallurgy; 1923 powder metallurgy carbide appears as the revolution in mechanical processing.

2, the thirties successful preparation of porous oil bearing; then powder metallurgy iron-based mechanical parts development, give full play to the powder metallurgy less cutting or even no cutting advantages.

3, to the more advanced new materials, new technology development. In the late 1940s, powder high-speed steel and powder superalloys appeared in the late 1960s and early 1970s.


在線咨詢

在線咨詢

欧美亚洲日韩欧美| 国内黄色看片| 九色在线78m| 91精品亚洲| 久久久久亚洲AV片无码V| 天天爽天天干| 最新亚洲蜜臀AV地址| 中文字幕av解说| 在线日韩网页| 无码高清2| 日本老熟妇xxxx| 国产色站在线| 日韩AV一区二区在线| 无码中文一二区| 国产精品一久久久| 国产免费综合一区二区| 香港少妇三级| www.人畜激情| 丁香七月A V| 国产成人久久综合电影| 国产XXXX99真实实拍| 久碰人妻人妻人妻人人掠| 秋霞一区二区三区在线| 精品久久无码中文字幕| 国产成人黄色精品| 久久成人久久久久| 亚洲AV三区| www.4444| 久鲁久久鲁| 欧美六月婷婷| 中文字幕日韩精品亚洲七区 | 国产成年无码久久久| 日韩精品30p| 99国产激情视频| 皇色在线你懂的| 熟妇50亚洲| 精品一区二区女色| 人人狠狠夜夜超碰| 色久悠悠乳| 二区无码三区| 大学生无套日出白浆|