Cutting tool of polycrystalline diamond and method of manufacturing the same

A polycrystalline diamond cutting tool prepared from a polycrystalline diamond layer being synthesized on a base material by a low-pressure vapor phase method, said polycrystalline diamond cutting tool comprising:

• a rake face having surface roughness of not more than 0.2 .mu.m at the maximum height of irregularities (R.sub.max);
• and
• a flank exposing a surface of said polycrystalline diamond having a graphite coating thereon.
• the size of cutting edge chipping along the intersection between said rake face and said flank being at least 0.5 .mu.m and not more than 5 .mu.m.

A polycrystalline diamond cutting tool prepared by employing a polycrystalline diamond layer being synthesized on a base material by a low-pressure vapor phase method as a tool material and connecting said tool material with a tool holder, said polycrystalline diamond cutting tool comprising:

• a rake face having surface roughness of not more than 0.2 .mu.m at the maximum height of irregularities (R.sub.max);
• and
• a flank exposing a surface of said polycrystalline diamond having a graphite coating thereon.
• the size of cutting edge chipping along the intersection between said rake face and said flank being at least 0.5 .mu.m and not more than 5 .mu.m.

The method of manufacturing a polycrystalline diamond cutting tool, comprising the steps of:

• depositing a polycrystalline diamond layer on a surface of a base material formed of one of metal and alloy having surface roughness of not more than 0.2 .mu.m at the maximum height of irregularity (R.sub.max) by a low-pressure vapor phase method;
• cutting said coated polycrystalline diamond layer being deposited on said base material, into a prescribed tip configuration and thereafter removing said base material from said polycrystalline diamond tip by chemical processing;
• and
• performing laser processing on a surface of said polycrystalline diamond tip intersecting with rake surface having been in contact with said base material, thereby forming a flank with depositing a graphite coating thereon.

The method of manufacturing a polycrystalline diamond cutting tool, comprising the steps of:

• depositing a polycrystalline diamond layer on a surface of a base material formed of one of metal and alloy having surface roughness of not more than 0.1 .mu.m at the maximum height of irregularities (R.sub.max) by a low-pressure vapor phase method;
• cutting said polycrystalline diamond, being deposited on said base material, into a prescribed tip configuration and thereafter removing said base material from said polycrystalline diamond tip by chemical processing;
• connecting said polycrystalline diamond tip with a tool holder so that a surface, having been in contact with said base material, of said polycrystalline diamond tip defines a tool rake face;
• and
• performing laser processing on a surface, intersecting with said rake face, of said polycrystalline, diamond tip for forming a flank;
• and depositing a graphite coating onto said flank.

The method of manufacturing a polycrystalline diamond cutting tool, comprising the steps of:

• depositing a polycrystalline diamond layer on a surface of a base material formed of one of metal and alloy having surface roughness of not more than 0.1 .mu.m at the maximum height of irregularities (R.sub.max) by a low-pressure vapor phase method;
• cutting said polycrystalline diamond, being deposited on said base material, into a prescribed tip configuration and thereafter removing said base material from said polycrystalline diamond tip;
• performing laser processing on a surface of said polycrystalline diamond tip intersecting with rake surface having been in contact with, said base material for forming a flank with deposition a coating of graphite thereon;
• and
• removing a graphite coating layer formed on said flank by said laser processing.

The method of manufacturing a polycrystalline diamond cutting tool, comprising the steps of:

• depositing a polycrystalline diamond on a surface of a base material formed of one of metal and alloy having surface roughness of not more than 0.2 .mu.m at the maximum height of irregularities (R.sub.max) by a low-pressure vapor phase method;
• cutting said polycrystalline diamond layer, being deposited on said base material, into a prescribed tip configuration and thereafter removing said base material from said polycrystalline diamond tip by chemical processing;
• connecting said polycrystalline diamond tip with a tool holder so that a surface, having been in contact with said base material, of said polycrystalline diamond tip defines a tool rake face;
• performing laser processing on another surface, intersecting with said rake face, of said polycrystalline diamond tip for forming a flank with depositing a coating of graphite thereon;
• and
• removing a graphite coating layer formed on said flank by said laser processing.

The method of manufacturing a polycrystalline diamond cutting tool, comprising the steps of:

• depositing a polycrystalline diamond layer on a surface of a base material by a low-pressure vapor phase method;
• cutting said polycrystalline diamond, being deposited on said base material, into a prescribed tip configuration and thereafter removing said base material from said polycrystalline diamond tip by chemical processing;
• defining a tool rake face by a surface, having been in contact with said base material, of said polycrystalline diamond tip and forming a flank with depositing a coating of graphite thereon at a prescribed angle with respect to said rake face, thereby forming a cutting edge portion;
• and
• honing said cutting edge portion for forming a curved surface.