Claims
- 1. A method of machining a metal comprising the steps of selecting a cutting tool having a cutting edge made of a material that retains its cutting effectiveness at temperatures over about 1200.degree. F., and having a side wear land surface and a side relief surface, the relief angle of the side land surface being substantially zero and the relief angle of the side relief surface being of a selected value, using the tool to machine the metal, selectively changing the width of the side land surface and the magnitude of the side relief angle as needed such that the width of the side land surface becomes substantially constant as the tool is used to machine the metal, and machining the metal with the cutting tool.
- 2. The method of claim 1 wherein the selecting step further comprises selecting a cutting tool having an effective rake angle defined substantially in accordance with the formula cos C = (l.sub.i /l.sub.f) cos D where C is the effective rake angle of the cutting tool, l.sub.i /l.sub.f is the ratio of the initial length to final length of a specimen of the metal being machined when tensile loaded to failure measured parallel to the applied load, and D is the neck down angle of the specimen in the failure area after being tensile loaded to failure.
- 3. The method of claim 1 wherein the selecting step further comprises selecting a tool having an end wear land surface and an end relief surface, the relief angle of the end wear land surface being substantially zero and the relief angle of the end relief surface being of a selected value, said method further comprising the step of selectively changing the width of the end land surface and the magnitude of the end relief angle as neded such that the width of the end wear land surface becomes substantially constant as the tool is used in machining the metal.
- 4. The method of claim 1 wherein the selecting step further comprises selecting the width of the side land surface so as to be not so narrow that the tool cutting edge chips during machining or so wide as to cause rubbing or chattering during machining.
- 5. The method of claim 1 wherein the selecting step further comprises selecting the relief angle of the side relief surface, prior to using the tool to machine said metal, to be approximately no greater than 22.degree., and the changing step further comprises increasing the magnitude of the side relief angle as needed such that the width of the side land surface becomes substantially constant as the tool is used to machine the metal.
Parent Case Info
This is a division of application Ser. No. 304,771, filed Nov. 8, 1972, which was a continuation-in-part of application Ser. No. 45,357 filed June 11, 1970, now abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
2164303 |
Berg et al. |
Jul 1939 |
|
Non-Patent Literature Citations (3)
Entry |
Article by Purser-- Bearing Lands and Negative Rakes --from American Machinist, Aug. 2, 1945, pp. 118-121. |
Article by Heinmann-- Cutting Force-- from The Tool Engineer, Mar. 1960, pp. 101-104. |
Article from ChXIII of Metal Cutting Tools by A. L. DeLeeuw, McGraw-Hill Book Co., T. J. 1185D44 P.O. Library, pp. 212-225. |
Divisions (1)
|
Number |
Date |
Country |
Parent |
304771 |
Nov 1972 |
|
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
45357 |
Jun 1970 |
|