污视频网站在线观看-日本a在线-av无码一区二区三区-中文字幕久久久久-女攻总攻大胸奶汁(高h)-精品无码一区二区三区的天堂-国产又粗又猛又黄又爽的视频-亚洲人天堂-亚洲视频免费播放-亚洲熟妇无码乱子av电影-日韩中文网-伊人手机在线视频-av福利片-亚洲综合色一区-白白色在线播放-九九色精品-男女视频一区-欧美性猛交xx乱大交-日韩欧美理论片-就去吻亚洲

全國熱線服務:

News 當前位置:首頁 > News > News >

Briefly introduce the commonly used methods for hardness testing of cold drawn tubes

Many customers who purchase cold-drawn pipe materials to make products have requirements for their hardness. For example, can the hardness of a certain specification of cold-drawn steel welded pipes meet the requirements?
Hardness is a performance index that measures the softness and hardness of a material. There are many methods of hardness testing, the principles are different, and the measured hardness values ??and meanings are also different. The most commonly used is the static load intrusion hardness test, that is, Brinell hardness HB, Rockwell hardness HRA, HRB, HRC, Vickers hardness H, etc. The hardness value indicates the ability of the material surface to resist the intrusion of hard objects. Leeb hardness Hl and Shore hardness HS belong to the rebound hardness test, and their values ??represent the elastic deformation work of the metal. Therefore, hardness is not a simple physical quantity, but a comprehensive performance index that reflects the elasticity, plasticity, strength and toughness of the material.  
The Rockwell hardness of cold drawn tubes is commonly used in machinery factories. It is a hardness test of parts after heat treatment, usually Rockwell hardness test. The Rockwell hardness test method for cold drawn steel is used because of its simplicity. Whether it is Brinell hardness or Vickers hardness, the test method requires measuring the diameter and diagonal length of the pit made by the indenter, which is very troublesome. The Rockwell hardness test method is the same as using an indenter to make pits, but the hardness value can be judged by the depth of the pits. Therefore, the testing machine can directly display the size of the pit without the need for measurement. As long as the test action of pressing with the indenter is used, the hardness value can be obtained.  

上一篇:Introducing the functions of solution treatment of high-precision cold drawn tubes

下一篇:A brief analysis of the reasons why piston rods are often damaged