- Contact Person : Mr. Cao Liam
- Company Name : Jinhua City Huazhong Welding Manufacturing Co., Ltd.
- Tel : 86-0551-3545458
- Fax : 86-0551-3545459
- Address : Zhejiang,JINHUA,Industrial Zone, Jinhua City, Huangshan
- Country/Region : China
- Zip : 321000
WELDING TIPS: SURFACE PREPARATION OF CARBON STEELS BEFORE BRAZING
1. The Brazability of Carbon Steel
Four kinds of oxides are formed on the surface of carbon steel. There are α-Fe2O3, γ- Fe2O3, Fe3O4(FeO •Fe2O3), and FeO. Except for Fe3O4, others are porous structure and unstable. Since all the oxides are easy to be got off by brazing flux, and reduced by reducing gas. The carbon steel, expeciallly the low-carbon steel has very goog brazability.
1. The Surface Preparation of Carbon Steel
In addition to mechanical method for removing the oxides from carbon steel , chemical wash ( acid cleaning) is particularly suitable for work pieces of mass production.
The water solution of sulphuric acid or hydrochloric acid can be used for getting rid off the oxides fron carbon steel, but the mix solution of both could bring the best brazing reults.
The common acid cleaning solution are:
1. 10% H2SO4 or 10%HCl water solution. Acid picking temperature:40-60 °C. Time:10-20 minutes.
2. 5%-10%H2SO4 or 2%-10% HCl water solution, plus 0.2% corrosion inhibiotr. Acid picking temperature: 20 °C. Time: 2-10 minutes.
Available Brazing Alloy:
BAg, BCup, HS221
WELDING TIPS: SURFACE PREPARATION OF CARBON STEELS BEFORE BRAZING
