US1545095A - Steel alloy - Google Patents

Description

ticles, that is to say articles which. in service and valve Patented July 7, lglzfi.

eaten.

DAVE 0'. GILES, 0F LATRGBE, PENNSYLVANIA.

s'rnnr. ALLOY.

Ho Drawing.

I To all whom it mag emocrat Be it known that l, DAVID J. GILES, a citi zen of the United States, and a resident of Latrobe, in the countyof Westmoreland and State of Pennsylvania, have invented a new and useful Improvement in Steel Alloys, of which the following is a specification.

The object of this invention is to provide a readily forgeable and otherwise workable steel alloy which may be economically manufactured and which, although unlimited to any particular use or uses, is peculiarly suitable for the manufacture of hot work arare subjected to repeated heating.

The steel alloy provided according to the invention includes tungsten or molybdenum, cobalt, chromium and carbon. It preferably contains no additional alloying elements except those that may be present as impurities. The amounts of these elements present in the alloy are from about 2.0 to 7.0% tungsten or molybdenum, preferablythe former, .2 to 5.0% cobalt, 2.0 to 8.0% chromium, and .2 to 1.5% carbon.v Silicon may also be added upto about 3.0%. The

several elements entering into the alloy may be present within about the ranges stated, although the preferred alloy contains about 0.0% oftungsten or molybdenum, 5% cobalt, 7.0% chromium, 0.8% silicon and l5% carbon. I

From an alloy of this preferred analysis there were manufactured valves, valveseats leeves for internal combustion engines which were subjected to severe tests and found to be much superior to the same parts manufactured from the best known prior commercial alloy used for the purpose. The standard test which is given to internal combustion engine valve parts is to subj'ect them to continuous use in an engine running at a high speed. lit is generally considered thata valve which will stand a test of one hundred hours duration without failin is unusually good. In the tests ofthe Va ves Application filed August 18, 1023. Serial;- No. 658,040. I

' made of the alloy explained above an engine was run for three hundredhours continuously, and when the valves were removed they were found to be in excellent condition.

Their surfaces did notshow any fire cracks or any signs of leakage. i

While the alloy provided according to this invention is peculiarly suitable for internal combustion engine valves, valve seats and valve sleeves, it is also well suited for the manufacture of other hot worlr articles, such as forging dies and dies for casting aluminum.

In the practice of the invention it will be understood that molybdenum may be used as an equivalent for tungsten.

I claim as my invention: 0

1. A steel alloy containing chiefly iron, and from about 2.0 to 7.0% tungsten, .2 to 5.0% cobalt, 2.0 to 8.0% chromium, and .2 to 1.5% carbon, the alloy being free from any additional element which would appreciably alter its high resistance to wear and to the development of fire cracks when used under high temperature service conditions.

2. A. steel alloyconsisting of from about 2.0 to 7.0% tungsten, .2 to 5.0% cobalt, 2.0 to 8.0% chromium, silicon not more than about 3.0%, and .2 to 1.5% carbon, and the remainder iron except for impurities.

3. A steel alloy containing chiefly iron, and about 6.0% tungsten, 5% cobalt, 7.0% chromium, and .45% carbon, the alloy being free from any additional element which would appreciably alter its resistance to wear and to the development of fire cracks when used under high temperature service conditions.

t. A. steel alloy consisting of about 6.0% tungsten, .5% cobalt, 7.0% chromium, 0.8% silicon, and .45% carbon, and the remainder iron except for impurities.

lin testimony whereof, ll sign my name.

' DAVID J. GILES.

Witness:

G. G. TRILL.