Three methods of overlay welding of Monel400 nickel-copper alloy

Monel400 is a commonly used nickel-copper alloy with good corrosion resistance, high strength, and excellent welding performance, Monel 400 is widely used in marine engineering and the chemical industry.

monel400 chemical composition:

Nickel (plus cobalt): ≥ 63.0

Carbon: ≤0.

Manganese: ≤2.

Iron: ≤2.

Sulfur: ≤0.02

Silicon: ≤0.5

Copper: 28.0 -34.0

In practical applications, the quality of the Monel 400 overlay is a key issue. In order to compare the effect of three different surfacing methods on the quality of Monel400 surfacing, three methods, namely CMT cold metal transition surfacing, electrode arc welding surfacing, and manual TIG surfacing, were used in this paper, and a number of tests and analyses were performed, including surface penetration testing, metallographic testing analysis, surfacing layer composition sweep analysis, dilution rate analysis, corrosion resistance analysis, shear strength analysis, and bending specimen analysis. The results show that all three methods can be used to obtain the results.

The results show that all three methods can obtain Monel 400 overlay layer with stable quality, among which the CMT overlay layer has the best quality. On the basis of CMT overlay, post-weld stress relief heat treatment was carried out, which proved that this method can effectively eliminate part of the residual stresses generated after overlay welding, making the overlay layer obtain better quality and reliability.

In summary, Monel 400 is a high-performance alloy material, and the optimization of its overlay quality is of great significance for practical applications. This paper compares three overlay methods and proves that the CMT overlay layer has the best quality, and also proposes an effective method for post-weld stress relief heat treatment, which provides a useful reference for practical production.