Ceramic milling cutter
AssigneeSandvik Intellectual Property AB
InventorsEmmanuel DAVID, Camille SANDALDJIAN
Life of this patent
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Abstract
A milling device is rotatable in one direction around a longitudinal center axis defining a forward direction and an opposite rearward direction, and includes a front part and a rear part. The front part has cutting edges, each having a longitudinal extension, and chip flutes, each having a longitudinal extension. The front part is made of a monolithic piece of ceramic. The rear part is configured to be fixed in a rotatable tool body or a rotatable chuck. The rear part is also made of a monolithic piece of cemented carbide. A front end surface of the rear part has a smaller area than a rear end surface of the front part. The front end surface of the rear part and a rear end surface of the front part are permanently bonded or brazed to each other by a joint.
Claims15
A milling device, rotatable in one direction around a longitudinal center axis defining a forward direction and an opposite rearward direction, comprising:
- a front part including a plurality of cutting edges, the front part having a longitudinal extension, the front part including a plurality of chip flutes each having a longitudinal extension, wherein the front part is made of a monolithic piece of ceramic;
- and
- a rear part configured to be fixed in a rotatable tool body or a rotatable chuck, wherein the rear part is made of a monolithic piece of cemented carbide, a front end surface of the rear part having a smaller area than a rear end surface of the front part, the front end surface of the rear part and a rear end surface of the front part being permanently bonded or brazed to each other by a joint.
A milling tool comprising:
- a milling device rotatable in one direction around a longitudinal center axis defining a forward direction and an opposite rearward direction, the milling device including a front part and a rear part, the front part having a longitudinal extension and including a plurality of cutting edges and a plurality of chip flutes, each having a longitudinal extension, wherein the front part is made of a monolithic piece of ceramic wherein the rear part is made of a monolithic piece of cemented carbide, a front end surface of the rear part having a smaller area than a rear end surface of the front part, the front end surface of the rear part and a rear end surface of the front part being permanently bonded or brazed to each other by a joint;
- and
- a rotatable tool body, the rear part having a thread and the rotatable tool body including a thread corresponding to the thread of the milling device, the rotatable tool body being made of steel, the thread of the rotatable tool body being an internal thread, the thread of the milling device being an external thread, and the rear part being configured to be fixed in a rotatable tool body or a rotatable chuck.
A method to produce a milling device, comprising the steps of:
- supplying a rear part of the milling device, the rear part being made of a monolithic piece of cemented carbide, the rear part having a longitudinal center axis defining a forward direction and an opposite rearward direction
- grinding a longitudinal front end surface of the rear part;
- blasting the front end surface of the rear part;
- cleaning the longitudinal front end surface of the rear part;
- supplying a cylindrically shaped front part made of a monolithic piece of ceramic having a circular surface defining a rear end surface of the front part, an area of the rear end surface of the front part being greater than an area of the front end surface of the rear part;
- cleaning the rear end surface of the front part;
- placing the front part such that the longitudinal center axis is in a vertical position;
- applying an active silver brazing filler metal on the front end surface of the rear part;
- positioning the front end surface of the rear part against the rear end surface of the front part;
- heating the front part, the rear part and the filler material to a temperature of 140-160° C. in 8-12 minutes;
- heating the front part, the rear part and the filler material to a temperature of 740-760° C. in 22-26 minutes;
- and
- grinding the front part in such a way that cutting edges and chip flutes are formed in the front part.
Dependencies are inferred from the claim text.