Monel 400 Alloy Introduction

The structure of Monel 400 alloy (UNS N04400, NCu30) is a high-strength single-phase solid solution. It is a corrosion-resistant alloy with the largest amount, the widest application and excellent comprehensive properties.

This alloy has excellent corrosion resistance in hydrofluoric acid and fluorine gas media, and also has excellent corrosion resistance to hot concentrated lye. It is also resistant to corrosion by neutral solutions, water, seawater, air, organic compounds, etc. An important feature of this alloy is that it generally does not produce stress corrosion cracks and has good cutting performance.

• Sheet standard: ASTM B127 ASME SB127
• Forging standard: ASTM B564 ASME SB564

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Chemical composition

Ni: >63; Cu: 28-34; Si: <0.5; Mn: <2.0; C: <0.30; Fe: <2.0.

This is a nickel-based alloy. Monel 400 alloy is also known as N04400. It is a corrosion-resistant alloy with large dosage, wide application and excellent comprehensive performance. This alloy has excellent corrosion resistance in hydrofluoric acid and fluorine gas media, and also has excellent corrosion resistance to hot concentrated lye. At the same time, it is resistant to corrosion from neutral solutions, water, seawater, atmosphere, organic compounds, etc. An important feature of this alloy is that it generally does not produce stress corrosion cracks and has good cutting performance.

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Typical Properties of Monel 400 Alloy

Property	Metric	Imperial
Density	8.8 g/cm3	0.318lb/in3
Melting point	1350°C	2460°F
Co-Efficient of Expansion	13.9µm/m.°C (20-100°C)	7.7×10-6 in/in.°F (70-212°F)
Modulus of rigidity	65.3 kN/mm2	9471 ksi
Modulus of elasticity	105-120 kN/mm2	15230-17405 ksi

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Properties of Supplied Materials and Heat Treated Materials

Condition of Supply	Heat Treatment (After Forming)
Annealed/Spring Temper	Stress relieve at 300-320°C (570-610°F) for 1 hour and air cool.
Condition	Approx Tensile Strength		Approx Service Temp.
Annealed	400 – 600 N/mm2	58 – 87 ksi	-200 to +230°C	-330 to +445°F
Spring Temper	850 – 1050 N/mm2	123 – 152 ksi	-200 to +230°C	-330 to +445°F

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Applications

Pipes made by Monel 400 alloy is a corrosion-resistant alloy with excellent comprehensive performance. Among fluorine gas, hydrochloric acid, sulfuric acid, hydrofluoric acid and their derivatives, the alloy has excellent corrosion resistance. The alloy is widely used in marine, chemical and other fields. Typical applications include: pumps and propeller shafts; marine devices and fasteners; chemical equipment; gasoline and fresh water tanks; crude oil stills; processing vessels and pipelines; boiler feedwater heaters; replacement Heater.

Posted by stainless steel pipe and fittings supplier, KAYSUNS