AM 350®
AM 350® is a versatile, semi‑austenitic stainless steel known for its unique ability to be strengthened through multiple pathways, including cold working, heat treatment, and precipitation hardening. This flexibility allows the alloy to deliver an impressive combination of high strength, toughness, and corrosion resistance, making it valuable in demanding aerospace and industrial environments. Its balanced chemistry provides stability across a wide temperature range, while its transformation‑hardening capability enables designers to tailor mechanical properties to specific performance needs. As a result, AM 350® is often chosen for springs, fasteners, structural components, and other parts that must endure both mechanical stress and corrosive conditions without sacrificing reliability.
Inventory Size Ranges for AM 350®
| Type | Thickness | Get a Quote |
|---|---|---|
| Precision Reroll Strip | 0.0008" - 0.015" | Get a Quote |
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Advanced Inventory Size Ranges for AM 350®
| Type | Size Range | Get a Quote |
|---|---|---|
| Get a Quote |
Characteristics of AM 350®
This alloy is austenitic in the annealed condition for good formability and transforms to martensite during cold work or heat treatment, enabling hardening. AM 350® achieves high tensile and yield strengths after hardening and maintains good toughness even at elevated strength levels. Additionally, this product has good corrosion resistance and performs well in many industrial and atmospheric environments.
Working with AM 350®
AM 350® machines well in the annealed condition, where it behaves similarly to austenitic stainless steels. This alloy is intentionally supplied in a condition that allows excellent formability before hardening. This product forms readily when annealed. Cold work induces martensitic transformation, increasing the alloy's strength. AM 350® offers several heat‑treating paths depending on the desired final properties. Annealing should be used for softening and formability. Precipitation hardening is used to achieve very high strength after forming. M 350® offers several heat‑treating paths depending on the desired final properties. When welding, use low-heat input to minimize distortion. Welding hardened material is not recommended due to cracking risks.
Other industry standards we comply with:
Common Trade Names
- AM-350
- Alloy 350
- Allegheny Ludlum Alloy 350
Industry Applications for AM 350®
- Springs
- Clips
- Fasteners
- Brackets
- Actuators
- Valve components
- Pump parts
- Surgical tools
Chemical Composition
| Element | Percent by Weight Min | Percent by Weight Max | |
|---|---|---|---|
| Cr | Chromium | 16.0 | 17.0 |
| Ni | Nickel | 4.0 | 5.0 |
| Mn | Manganese | - | 1.0 |
| Si | Silicon | - | 1.0 |
| C | Carbon | 0.08 | 0.12 |
| N | Nitrogen | - | 0.07 |
| P | Phosphorus | - | 0.040 |
| S | Sulfur | - | 0.030 |
| Fe | Iron | - | Balance |
Datasheet
Additional Info
A Brief History of AM 350®
AM 350® emerged in the mid‑20th century as aerospace and defense industries began demanding stainless steels that could offer both high strength and reliable corrosion resistance. Traditional martensitic and austenitic stainless steels each had strengths, but neither could deliver the combination of formability, toughness, and post‑fabrication hardening flexibility that engineers needed. Metallurgists developed AM 350® as part of a new class of semi‑austenitic precipitation‑hardening stainless steels, designed to bridge the gap between easy‑to‑form alloys and high‑strength structural materials.
How AM 350® was Developed
The alloy was engineered by carefully balancing chromium, nickel, and molybdenum to create a structure that is austenitic when annealed but capable of transforming into martensite during cold work or controlled heat treatment. This transformation‑hardening capability, combined with precipitation hardening, allowed AM 350® to reach strength levels far beyond conventional stainless steels. Its development focused on giving manufacturers the freedom to shape components first and strengthen them later, a major advantage for complex aerospace parts.
Early Applications of AM 350®
Early adopters of AM 350® were primarily in the aerospace and military sectors, where the alloy’s unique combination of formability and high strength was immediately valuable.
- Aircraft springs and diaphragms
- High-strength fasteners
- Structural brackets and hardware
How AM 350® is Used Today
Today, AM 350® remains a versatile material across multiple industries.
- Aerospace: Springs, bellows, fasteners, precision components
- Industrial: Blades, valve parts, pump components,
- Defense: Actuators, structural elements, high-strength mechanisms
Your Trusted Supplier of AM 350®
United Performance Metals supplies AM 350® precision rerolled strip sizes 0.0008" - 0.015". Its combination of formability, strength, and corrosion resistance keeps it relevant in modern engineering, especially where designers need a stainless steel that can be tailored to specific performance requirements.
Product FAQs
AM 350® can be strengthened by cold working, transformation hardening, and precipitation hardening.
In the annealed condition, it is mostly non‑magnetic. After cold work or transformation hardening, it becomes magnetic due to the formation of martensite.