US 3804761 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
United States Patent U.S. Cl. 252-30 1 Claim ABSTRACT OF THE DISCLOSURE Addition of calcium molybdate or magnesium metaborate to lead-containing forging lubricants.
BACKGROUND OF THE INVENTION (1) Field of the invention This invention relates to forging lubricants. More particularly, it relates to a forging lubricant capable of withstanding 800 F. or higher forging temperatures.
(2) Description of the prior art is particularly true where premium strength aluminum' forgings are produced and where the tools often reach the 800 F. and higher, e.g. when titanium stock is heated to 1500 F.-2000 F. prior to forging. Often an undesirable amount of aluminum pickup on the tools is encountered when prior art lead-containing forging lubricants are used. Also, particularly in forging cups, an undesirably high pressure is required when forging lubricants known to date are employed.
SUMMARY OF THE INVENTION After extended investigation we have found that addition of calcium molybdate and/or magnesium metaborate to lead-containing forging lubricants provides a solution to the foregoing problems. We prefer to add from about 0.5 to about percent by weight calcium molybdate or magnesium metaborate to the lubricant. One or both of these additives may be used according to our invention, if desired. Calcium molybdate and magnesium metaborate are particularly useful when employed in a lead-based forging lubricant which also contains graphite. The lead may be present in almost any form, for example, oil of lead, lead naphthenate, or other forms such as covered by U.S. Pat. Nos. 485,688, 492,750, 494,433, 494,156, 520,498, 923,304 and 1,309,618 the disclosures of which as to inclusion of various forms of lead in lubricants are incorporated herein by reference thereto including specific reference to representative lead-containing substances including lead, white lead, red lead, the oxides, glycerates and carbonates of lead and the equivalents thereof. The preferred amount of calcium molybdate, magnesium metaborate, or both added according to our invention is from about 4 to about 6 percent by weight. The preferred dispersing agent, with additional lubricatin power, for the lead and other additives, as known for use in prior art forging lubricants, is an organic solvent dispersant such as mineral oil. The solvent or solvents usually make up at least about 50 percent 3,804,761 Patented Apr. 16, 1974 ice by weight of the lubricating composition. Our preferred forging lubricant contains from about 1 to about 5 percent by weight lead (measured as elemental lead), from about 1 to about 10 percent by weight graphite and from about 0.5 to about 10 percent by weight of at least one compound selected from the group consisting of calcium molybdate and magnesium metaborate.
The forging lubricant may be applied in the vicinity where the metal forged comes in contact with the die or other forging tool by brushing, spraying or the like.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The following examples are illustrative of the invention.
EXAMPLE 1 The following composition was employed as a forging lubricant in forging cups from aluminum, using 800 F. tools.
5.5 gallons of mineral oil, viscosity 2150 SSU at F.; 0.5 gallons of lead additive (lead naphthenate);
5 pounds of graphite; and
2.7 pounds calcium molybdate A 20 percent reduction of pressure required in forging cups was brought about by using this composition instead of one which did not contain the calcium molybdate.
EXAMPLE 2 Substantially the same composition as that of Example 1 was employed in forging aluminum cups at 800 F. except for use of magnesium metaborate in place of the calcium molybdate. A similar reduction of pressure was brought about over that required for forging comparable cups using as lubricant one which did not contain the magnesium metaborate.
In the preceding examples there was substantially no pickup of aluminum on the tools, and the lubricant residues were easier to clean from the tools where the calcium molybdate and magnesium metaborate were used in the lubricant.
While the invention has been described in terms of preferred embodiments, the claim appended hereto is intended to encompass all embodiments which fall within the spirit of the invention.
Having thus described our invention and certain embodiments thereof, we claim:
1. A forging lubricant comprising a major proportion of mineral oil, from about 1 to about 5 percent of at least one lead component selected from the group consisting of lead, white lead, red lead, the oxides, glycerates and car bonates of lead, lead naphthenate and oil of lead, and from about 0.5 percent to about 10 percent of at least one compound selected from the group consisting of calcium molybdate and magnesium metaborate.
References Cited UNITED STATES PATENTS 2,345,198 3/ 1944 Hodson 252-22 2,987,476 6/ 196 1 Hartley 252-18 3,453,209 7/1969 Sibcrt 252--25 PATRICK P, GARVIN, Primary Examiner A. H. METZ, Assistant Examiner U.S. Cl. X.R. 252-18, 23, 30