S240 Bar / Rod / Wire Special Alloys For Aerospace And Defense Tensile Strength 240ksi

Alloy S240 (UNS S11900) bar, shapes, rod, wire, forging for jet engine, land vehicle component, sophisticated armor etc
 
1 PRODUCT
Alloy S240 (UNS S11900) bar, shapes, rod, wire, forging for jet engine, land vehicle components, sophisticated armor etc.
Alloy S240 is available in following standard semi-finished forms:
Bar and Rod
Delivery condition: Forged, rolled, drawn, heat treated, oxidized, descaled or pickled, turned, peeled, ground or polished
Shape and profile
Rolled and extruded, cold drawn, oxidized, descaled or pickled
Wire (profile, round, flats, square)
Delivery condition: Drawn bright, ¼ hard to hard, bright annealed in rings, containers, on spools and headstocks
Wire rod
Delivery condition: hot rolled (dia.5.5mm to 40mm)
Others
Other shapes and dimensions such as discs, rings, seamless pipes and forgings can be requested.
 
2 EQUIVALENT DESIGNATION
UNS S11900, ATI S240® Alloy
 
3 OVERVIEW

Alloy S240 is a martensitic precipitation-hardening stainless steel with tensile strength of 240 ksi (1655 MPa), high fracture toughness, and good corrosion and stress corrosion cracking resistance. Alloy S240 has strength and toughness properties that are comparable to other commercial steels in this class, but it also offers:

◘ Simple processing; can be thermal mechanically processed similarly to other precipitation-hardened stainless steels such as 13-8 and 15-5 alloys, and does not require “deep freeze” or cryogenic treatment to achieve the high tensile strength

◘ Improved corrosion and stress corrosion cracking resistance compared with other steels of similar strength

◘ Lower raw materials and processing costs (no cobalt; no complicated heat treatment)

Good transverse toughness properties are achieved by tight chemical composition control, low carbon content, and double vacuum melting. The alloy is produced by vacuum induction melting (VIM), followed by vacuum arc remelting (VAR).This melt practice ensures excellent macro- and micro-cleanliness, and tight compositional control. The strengthening mechanism (precipitation hardening in a martensitic matrix) makes it possible to achieve uniform strengthening in heavy sections. Strength and ductility levels can be tailored to the application by varying the aging temperature.
 
4 APPLICATION

Defense

(Our specialty materials play a key role in supporting this effort — in jet engines; structural components for land vehicles; systems for ships; and sophisticated armor that protects systems and people when they’re in harm’s way.)

Offshore platform, helicopter deck other platforms

Food processing

Pulp and paper industry

Aerospace

Mechanical components

Oil field

Chemical process components

General metalworking industry
 
5 CHEMICAL COMPOSITION (wt%):

 
6 PHYSICAL PROPERTY
Melting range:2560 - 2680ºF (1404 - 1471ºC)
Density: 0.281 lb/in³ (7.77 g/cm³)
Elastic Modulus: 26.0 Msi (179.3 GPa)
Specific heat, thermal conductivity and thermal expansion

 
7 MECHANICAL PROPERTIES
Average mechanical properties (all tests done at room temperature)

 
8 CORROSION RESISTANCE

 
9 WORKING INSTRUCTION
Formability
Alloy S240 has good hot working characteristics which are comparable with other steels in this class. Forging can be performed at temperatures from 1600°F to 2200°F (871°C to 1204°C) with optimum properties achieved with forging at temperatures less than 2000°F (1093°C). After forging, parts should be cooled to room temperature, then solution treated prior to aging. The alloy can be cold formed in annealed condition, utilizing conventional cold forming techniques.
Heat treatment
Solution treatment should be performed from 1675ºF to 1725ºF (913ºC to 941ºC) for 45 to 75 minutes at temperature followed by cooling to 32ºF (0ºC) and holding for at least four hours to ensure complete transformation to martensite. No “deep freeze” or cryogenic processing is required.
Aging is normally carried out from 950ºF to 1150ºF (510ºC to 621ºC), depending upon the desired final properties. Heat treatment is usually performed in air. Heat treatment of brazed components may be done in inert atmospheres. Reducing atmospheres should not be used because of the potential for nitrogen contamination.
Hardness

Machinability
Alloy S240 can be machined in both the annealed and hardened conditions. In the annealed condition, use machine speeds 20 to 30 percent lower than those used on 304 stainless steel.
 
10 STANDARD SPECIFICATION
AMS 5929 Bar and forging
 
11 COMPETITIVE ADVANTAGE:
(1) More than 50 years experience of research and develop in high temperature alloy, corrosion resistance alloy, precision alloy, refractory alloy, rare metal and precious metal material and products.
(2) 6 state key laboratories and calibration center.
(3) Patented and innovative technologies.
(4) Ultra-purity smelting process: VIM + IG-ESR + VAR
(5) Excellent high performance.
 
12 BUSINESS TERM