Bine ati venit Vizitator ( Logare | Inregistrare )

Reply to this topicStart new topic
> Fr Soft Strip Bushing Oil Sintered Bearing,oilite Bearing, FR soft strip bushing oil sintered bearing,oilite bearing
postare Mar 9 2017, 05:22 AM
Postare #1


Grup: Members Plus
Postari: 20
Inscris la: 21-February 17
Membru nr.: 238,845

Welding characteristics of steel and copper, carbon steel welding

Weldability is refers to the material in a limited amount of construction under the condition of replacement shock bushings into the design requirements in accordance with provisions of artifacts, and ability to meet the requirements of reserve service.Weldability by material, welding method, the component type and use requirement of four factors.Carbon steel is based on iron, iron carbon alloy, carbon as alloy elements, its carbon mass fraction of less than 1%, in addition, the mass fraction of manganese is not more than 1.2%, more than 0.5% mass fraction of silicon, the latter two are not as alloying elements.Other elements such as Ni, Cr, Cu, etc are controlled in the residual volume within the limits of the less as alloying elements.Impurity elements such as S, P, O, N, according to different varieties and grades of steel, are strictly limited.Carbon steel weldability, therefore, depends on carbon content, with the increase of carbon content, weldability worse gradually, with the best weldability of low carbon steel,

The FR soft strip bushing of steel and copper features:

Fe and Cu in the atomic radius, lattice type, lattice constant and the outer electrons are close to the welding between the steel and copper.However, the fusion welding of steel and copper has certain difficulty, mainly as follows:

(1). The physical properties of the steel and copper, melting point and linear expansion coefficient difference is big.The linear expansion coefficient of copper, will generate a large welding stress in the welding process.

(2). The coefficient of thermal conductivity of copper is more than 8 times of steel, the cooling speed of molten pool is much bigger than the steel, the diffusion of hydrogen evolution and water floatation condition is more severe, the sensitivity of the formation gas empty.

(3). In the weld seam or near area is easy to produce hot crack, which affect the strength of the joint and air tightness, this is the key to solve the problem of welding technology.Because - quantitative impurity is contained in steel and copper, such as oxygen, sulfur, phosphorus, etc.In the welding process is called, the impurity elements easy to form a variety of low melting eutectic and brittle compounds and in welding seam grain boundary, the metal at high temperature was severely weakened intergranular binding force, is the main cause of hot cracking formation of weld.In addition, the oil sintered bearing,oilite bearing in weld has a great impact on hot cracking tendency.According to the relevant information, when the iron content in 10 ~ 43%, the weld has the best crack resistance.Therefore, control of weld fusion ratio is quite important link.
  Daca iti place acest topic recomanda pe facebook :
Go to the top of the page
+Quote Post

Reply to this topicStart new topic


RSS Versiune Lo-Fi Acum este ora: 10th April 2020 - 01:40 AM