Austenitic Nickel-Base Weld Alloy for Hot Crack Resistance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Nickel-base alloys used as weld metals for corrosive applications have insufficient hot cracking resistance, leading to poor strength and ductility, and impaired corrosion resistance when hot cracks form.

Innovation Solution

An austenitic nickel-based alloy with specific composition ranges (C≤ 0.03, Si≤ 1.0, Mn≤ 1.5, P≤ 0.03, Cr 25.0 to 29.0, Ni 42.0 to 52.0, Mo 6.0 to 9.0, N 0.07 to 0.11, and optional Al, Mg, Ca, Ce, B) that reduces total crack length to less than 2.5 mm during Varestraint testing, enhancing resistance to hot cracking and corrosion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If high-alloy austenitic steel is used with high Cr and Ni content, then corrosion resistance is improved, but hot cracking susceptibility increases

Engineering Contradiction:
Improvecorrosion resistanceVSAvoidhot cracking susceptibility
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent optimizes the alloy composition parameters by setting Cr to 25.0-29.0% (avoiding excessive Cr that would increase hot cracking), Mo to 6.0-9.0% (providing corrosion resistance without excessive alloying), and C to ≤0.03% (limiting carbon to prevent carbide precipitation that promotes hot cracking). The specific parameter ranges are carefully selected to achieve the optimal balance between corrosion protection and hot cracking resistance.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite alloy system combining multiple elements (Cr, Mo, Ni, Mn, Si, P, S, N) in specific proportions to achieve properties that cannot be obtained by single elements alone. The synergistic combination of Cr (25.0-29.0%) for corrosion resistance, Mo (6.0-9.0%) for pitting resistance, and controlled C (≤0.03%) to prevent carbide formation creates a composite material structure that simultaneously provides corrosion protection and hot cracking resistance.

Inventive Principle:
Principle #40Composite materials

Data Source

PatentEP3797013B1An austenitic nickel-base alloy
Publication Date: 2022.02.23 SANDVIK MATERIALS TECH
  • EP3797013B1 patent drawingFigure 1~2

AI summary

The present disclosure relates to an austenitic nickel-base alloy having a high content of Ni, Mo and Cr which is suitable for use as a weld metal. Weld metal containing the present austenitic nickel-base alloy will have a high resistance to the formation of hot cracks. The present disclosure also relates to an object comprising the austenitic nickel- base alloy and to a weld metal comprising the austenitic nickel-based alloy. Further, the present disclosure also relates to a use of the present austenitic nickel-based alloy.