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AMS 6349 (4140)AMS 6349 (4140)

Chromium-Molybdenum Alloy Steel Bar

This chromium-molybdenum alloy is a deep hardening steel used where strength and impact toughness are required.

It has high fatigue strength making it suitable for critical stressed applications at normal as well as elevated temperatures. For increased resistance to wear and abrasion, it may be nitrided. This grade is a quality product melted under the best of steelmaking practices for aircraft quality steels. It is vacuum degassed to meet the magnetic particle inspection standards of AMS 2301. The alloy is supplied in the normalised and cold finished, hot finished and normalised or normalised and cold finished condition.

The density of this material is typically 7.85kg/dm³.

Technical Assistance

Our knowledgeable staff and resident metallurgists will be pleased to assist you further on any technical topic. Smiths Metal Centres Limited also boasts an in-house UKAS Accredited Testing Laboratory which is unique within the multi-metal and plastic stockholding sector. We believe this underlines our total commitment to quality and our ethos of being the complete service provider.

Download AMS 6349 (4140) Datasheet

Typical Applications:

Intended for general use for parts with sections ½” or less in thickness at time of heat treatment which require a through-hardening steel capable of developing hardness as high as Rockwell “C” 50; also for fittings and forgings of greater hardness or variation in thickness at proportionately lower hardnesses.

It is frequently used in applications in which 8640 (MIL-S-6049) is specified.

We offer AMS 6349 (4140) in round bar, hollow bar, plate, hexagon and flat bar. We offer processing services throughout the Smiths Group - with more than 30 band saws and a fully automated magazine feed CNC rod blanking line, we can process your material to your exact requirements.

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