Heat-Resisting Cast Ni-Cr-FE Alloys: Unlocking Performance in Demanding Environments

When equipment faces continuous high-temperature exposure—whether in kilns, furnaces, exhaust systems, or chemical process plants—the choice of material becomes critical. Not all steels are created equal. That’s where heat-resistant cast alloys, particularly those based on Nickel-Chromium-Iron (Ni-Cr-Fe) systems, can provide the decisive edge.

At Malabou, we work with Industrial Clients and OEMs to harness the metallurgical strengths of these alloys, delivering components that stand up to thermal shock, scaling, and creep where conventional steels fail.

Why Ni-Cr-Fe Alloys?

The unique balance of nickel, chromium, and iron provides several high-temperature benefits:

 Oxidation resistance – Chromium forms a stable oxide layer that resists scaling at temperatures above 1000 °C.

 Creep strength –Nickel strengthens the matrix, maintaining integrity under sustained thermal stress.

 Microstructural stability –Alloy design prevents grain coarsening, preserving toughness even after long service exposure.

 Versatility in casting –These alloys are ideally suited for complex shapes and large-scale castings, reducing welds and fabrication risks.

Applications in Industry

Ni-Cr-Fe cast stainless alloys are widely used in industries where reliability at elevated temperatures is non-negotiable:

 Mining & minerals processing –burner nozzles, kiln segments, rabble arms.

 Energy & power generation – furnace grates, heat exchanger parts, reformer tubes.

 Chemical & petrochemical – manifolds, retorts, and high-temperature ducting.

 OEM equipment – customised cast components replacing multi-weld fabrications.

Casting vs. Fabrication: The Metallurgical Edge

Fabricated high-temperature components often fail prematurely due to weld cracking and inconsistent metallurgy. Monolithic castings in Ni-Cr-Fe alloys eliminate these weak points, offering:

 Uniform composition across the part.

 Greater resistance to thermal cycling and fatigue.

 Reduced downtime and maintenance costs.

Malabou’s Expertise

Malabou cast special alloys that allow for castings to be used at elevated temperatures, in some cases in excess of 1000°C.

These heat-resistant casting alloys consist predominantly of combinations of nickel, chromium and iron together with small percentages of other elements.

Castings made of these high temperature alloys exhibit good mechanical strength and toughness at elevated temperatures as well as oxidation and corrosion-resistance in environments at temperatures where they are to be used.

Malabou can also select the advanced casting method to best help clients achieve the right balance of performance, reliability, and cost-effectiveness including investment, sand and shell moulding.

Temperature Casting Classifications

The common designations for cast alloys are descriptive of their chemistry and purpose. This designation system was established by the Alloy Casting Institute (ACI) and has been adopted by ASTM.

The Alloy Casting Institute designations use “H” to indicate alloys generally used in applications where temperature is more than 537°C (1000°F). The second Letter represents the nominal nickel content, increasing from A to X.

Heat-resistant casting alloys are classified per metallurgical structure and composition it to three groups:

Chromium-Iron alloys: e.g. HA, HC, HD

Chromium-Nickle-Iron alloys: e.g. HE, HF, HH, HI, HK,HL

Nickel-Chromium-Iron alloys: e.g. HN, HT, HU, HW, HX

Heat is one of the toughest challenges in engineering. With the right alloy and casting approach, it doesn’t have to be a weak point.

Explore how Malabou can support your next project at www.malabou.com