US1943347A - Spring steel - Google Patents

Description

Patented Jan. 16, 1934 1 ,UNITED STATES SPRING STEEL Joseph Kent Smith, Detroit, Mich., assignor to The Beryllium Corporation, New York, N. Y., a corporation of Delaware No Drawing. Application August 10, 1931 Serial No. 556,324

'2 Claims. (01. 75-1 This invention relates to a series of compositions of steel characterized by high tensile strength, great flexibility and extremely high fatigue resistance, the essential feature of all mem- 5 bers of the series being the presence of metallic beryllium, always in quantities less than 5% of thetotal, and preferably less than 1% of the total.

In addition to iron and carbon, present in all in steels, and the beryllium which is the parent alloying substance of my invention, I have found it necessary, for best results, to add one or more of the metals chromium and molybdenum. While I do not mean to be limited to such compositions,

I have found that when molybdenum is used, best results are obtained when the carbon content is kept under 0.80%. Similarly, when chromium alone is present without any'molybdenum, the carbon had best not exceed 0.70%, and when both molybdenum and chromium are present in the alloy, carbon of 0.50% had best not be exceeded.

The usual steel constituents, manganese and silicon, are, of course, also present, the manganese frequently rising into the range of 1.0% to 1.5%, where it, too, may be considered an alloying element. The steels of the series of my invention lend themselves readily to substantially the heat treatment standard for steel of the corresponding carbon content.

One simple example of the invention is a spring steel of the composition for which the invention is especially useful.

Per cent Carbon 0.35 Chromium 1.00 Molybdenum 0.35 Manganese 1.00 Beryllium 0.30

In general, chromium, molybdenum and mananese are best held under 1.5% each.

I claim:-

1. Spring steel comprising carbon approximately 0.35%, chromium approximately 1.00%, molybdenum approximately 0.35%, manganese approximately 1.00% and beryllium approximately 0.30%, and the balance iron.

2. A steel comprising from about 0.30% to 7 about 5% beryllium; about 0.35% but not more than 1.5% molybdenum; about 1% but not more than 1.5% chromium; about 0.35% but not more than 0.50% carbon; about 1% but not more than 1.5% manganese; and the balance iron.

JOSEPH KENT SMITH.