Material Selection Guide

Carbon Steel

Carbon Spring Temper Steel

SAE 1070-1090 high carbon blue tempered and polished spring steel is a standard material for both rings and springs. It is the lowest cost material and best suited for applications that have a protected environment, as carbon steel corrodes if not lubricated or atmospherically sealed. Additional corrosion protection can be added with a special finish. Products are supplied with an oil dip finish providing adequate protection for shipment and shelf storage. Carbon steel is highly magnetic and is typically blue in color.

Stainless Steels

302 Stainless Steel

302 is the standard stainless steel for retaining rings. This widely used material is specified because of its combination of corrosion resistance and physical properties. 302 obtains its spring temper condition by cold working. Though it is categorized as being a nonmagnetic stainless, 302 becomes slightly magnetic as a result of cold working. It is not hardenable by heat treatment. 302 has a silver-gray color.

316 Stainless Steel

316 is also a standard material for retaining rings. Nearly identical in physical properties and heat resistance to 302, 316 provides additional corrosion resistance, particularly against pitting, due to its molybdenum chemical content. 316 is generally used in food, chemical and sea water applications. 316 has lower magnetism than 302. This stainless grade is also not hardenable by heat treatment. 316 has a silver-gray color.

17-7 PH/C Stainless Steel

Similar in corrosion resistance to type 302, this alloy is a standard for wave springs. Spring properties are achieved by precipitation hardening. As a Result, the material may be subjected to a temperature of 650° F without a loss of spring properties. 17-7 PH C/CH-900 exhibits magnetism similar to high carbon steel. After precipitation hardening, 17-7 has a blue to brown color, although atmosphere controlled heat treatments provide a bright color.

Super Alloys

Inconel X-750

This nickel-chromium alloy is used most commonly in high temperature and corrosive environments. Two tempers exists, the most common Inconel X-750 is precipitation heat treated to a spring temper condition. In this state, it has temperature resistance to 700° F. The National Association of Corrosion Engineers (NACE) approves this hard temper to Specification MR-01-75 (R_c 50 maximum) for spiral retaining rings and wave / compression springs. #1 temper has a lower tensile strength but provides temperature protection to 1000° F. Both spring temper and #1 temper may be heat treated in either an open air or atmosphere controlled furnace. Open air heat treatment may produce oxidation which often results in a black ash residue. An atmosphere controlled environment eliminates oxidation and produces a component with no residue. Rings and springs manufactured from Inconel have a blue / silver-gray color and exhibit no magnetism.

A286 Alloy

In applications up to 1000° F, this alloy exhibits similar properties to Inconel X-750 spring temper. Its spring temper condition is obtained by precipitation hardening. This material exhibits no magnetism and has a blue / silver-gray color.

Elgiloy

Known for its excellent resistance to corrosive environments, elevated temperature resistance and high strength. Elgiloy exhibits no-magnetism and is blue / brown in color as a result of heat treatment.

Coppers

Beryllium Copper Alloy #25

This alloy produces excellent spring properties due to a combination of low modulus of elasticity and high ultimate tensile strength. The alloy gains its physical properties by precipitation hardening. Beryllium copper is non-magnetic. Its electrical conductivity is about 2-4 times as great as phosphor bronze.

Phosphor Bronze, Grade A

Phosphor bronze offers electrical conductivity and fair spring properties. It is purchased in spring temper condition to maximize spring characteristics. Phosphor bronze is hardenable only by cold working. This material is nonmagnetic.