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    +44(0)1767 604555
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We are specialists in engineering materials support to improve the aerospace MRO supply chain.

Smiths MRO is a sub-divsion of a larger business - Smiths Advanced Metals.

Smiths MRO focuses on raw material support for the global aircraft maintenance, repair and overhaul market. Our business is supported by a broad and diverse stock range with a dedicated team that provides outstanding service levels required for our industry.

We offer AOG support (Aircraft on the Ground).

Type 440 Bar (AMS 5630)

Stainless Steel

440 stainless steel bars provide excellent wear resistance after heat-treatment.

440 stainless steel represents a series of stainless steel aloys which contain chromium and nickel.

440 stainless steel features a range of alloy variations, including 440A, 440B, 440C and 440, although 440C is the most common. All the alloys in this range are magnetic. Smiths MRO stocks 440B and 440C with the option to source and supply other products in this series if your lead-time allows it.

About 440C

440C is the most popular product available due to the material's overall hardness (a Rockwell Collins hardness of 58). AMS 5630 represents the most common material specification, and we supply the product in the annealed condition, also known as 'condition A'. After heat-treatment, this martensitic stainless steel achieves the highest strength and wear resistance of all stainless steel alloys. When compared to popular austenitic grade materials, the corrosion resistance of the alloy is somewhat reduced.


The strength and hardenability of the alloy results in a material which finds suitability in a broad range of commercial aerospace applications. Such applications include aircraft parts, bearing assemblies, needle and ball check valves and valve seats.

Stock Range

Smiths MRO stocks 440 series stainless steel bars in sizes from 0.5" (6.35mm) diameter up to 4" (101.6mm) diameter, with many sizes available in between. We supply this material to AMS 5630.

As a dedicated engineering materials support company for the global MRO sector, we offer a rapid turnaround on products with stocked materials often dispatched on the same day of purchase. We offer this service irrespective of your International location.

Product Features:

    AMS 5630

    Bearing assemblies
    Valve seats
    Aircraft Parts
    Needle and ball check valves

    Excellent hardenability
    Excellent strength
    Easily machined in the annealed condition
    High wear resistance

Do you require
440 Stainless Bar?

Smiths MRO

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