Sumitomo Electric manufactures and sells a variety of industrial material products and substrates for R&D, including "SUMICRYSTAL", one of the world's leading high pressure, high temperature (HPHT) synthetic diamond single crystal, and "SUMIDIA", a sintered diamond.
SUMICRYSTAL is synthetic diamond single crystal which Sumitomo Electric succeeded in mass production for the first time in the world. SUMICRYSTAL manufactured under strict quality control has stable quality, so it’s suitable for industrial materials or substrates for R&D.
Production Method
The synthetic diamond single crystal SUMICRYSTAL is synthesized in a superhigh pressure chamber from 5 to 6GPa and high temperatures from 1,300 to 1,600°C. The temperature difference between the raw carbon and the seed crystal is used to grow the diamond on the seed crystal. Through this strict control of pressures and temperatures, a more stable structure with minimal inclusions can be obtained.
Ultra-High Pressure Apparatus
Properties
SUMICRYSTAL has 4 main advantages over natural diamond. 1) Structural advantage: Natural diamond is rounded and the crystal orientation is difficult to determine with the naked eye. SUMICRYSTAL, however, has a distinct crystal face which makes the identification much easier. 2) Uniformity: Due to the strictly controlled conditions in which the crystals are grown, uniform quality is obtained consistently. 3) Availability: Unlike the limited supply of natural diamonds, SUMICRYSTAL can be mass produced. 4) SUMICRYSTAL diamond type Ib, which is used for tools, has mechanical and thermal properties equal to or even greater than natural diamond, while containing small amounts of nitrogen.
Fracture Strength
The micro-crack strength of SUMICRYSTAL exhibits approximately 25 GPa, SUMICRYSTAL stably comparable to those of the highest level of natural diamonds. The above outstanding properties demonstrate that SUMICRYSTAL is the best cutting tool material to withstand high stresses. *Micro-Crack Fracture Strength: Strength measured by Hertz fracture strength test method. In this method, a diamond indenter with a 5 μm radius tip is pressed against the surface of the test specimen and the pressing load is increased until the first crack appears on the surface. The micromechanical fracture strength is determined from the load that created the first crack.
Wear Resistance
The wear resistance of a diamond single crystal differs depending on the crystal orientation. Taking advantage of these wear characteristics, we manufactures a variety of SUMICRYSTAL products having different crystal orientations. *Crystal orientation and wear resistance: The wear resistance of (110) face <110> direction (abbreviated as “(110)<110>”) is 100 times or more than that of (100)<100>. However, since wear resistance differs significantly depending on the processing condition, the plane direction most appropriate for the actual processing conditions should be chosen.
"SUMIDIA WD" is a material with outstanding characteristics by on our unique structure formation and ultra-high pressure sintering technology. SUMIDIA achieves stable quality by thorough control from raw materials to the final inspection process.
Features
A material with outstanding characteristics by on our unique structure formation and ultra-high pressure sintering technology.
Excellent breakage resistance Because of firmly bonded polycrystalline structure, SUMIDIA WD eliminates the cleavage faults found in Single Crystal diamond.
Excellent wear- resistance SUMIDIA WD offers superior wear resistance, uniform wear and exellent fracture strength.
High quality polished surface The homogeneity of sintered body is implemented in our original technology. The diamond content ratio in sintered body is increased and each diamond grain is firmly bonded. SUMIDIA WD has high quality polished surface.
Series
SUMIDIA WD has 3 series such as with support-ring, with heat resistance.
The WD700 series are self-supported die blanks. These blanks are suitable for all types of wire drawing applications.
The WD800 series(Heat-Resistant type) are self-supported thermally stable blanks. These blanks are especially suited for applications which require high temperature in mounting and need high heat resistance in drawing.
The WD900 series are reinforced by a special outer ring. This feature make it possible to draw not only copper and aluminum wire but high tensile steel wire as well.
Grades
SUMIDIA WD has 5 grades: F, S, M, C, and E.
F Grades
Ultra fine （Extra-Fine:1μm） It is suitable for drawing dies that require a high quality surface finish or high fracture strength.
S Grades
Fine （Fine:3μm） It is standard grade of small diameter die blanks with support ring.
M Grades
Middle （Middle:5μm） It is effective for a wide variety of applications offering high finish with good wear resistance.
C Grades
Coarse （Coarse:12μm） It is suitable for drawing dies that require a high wear-resistance.
E Grades
Extra-coarse （Extra-Coarse:25μm）
Product No. Selection Guide
The description is a combination of series, grade and size.
1) Choose series.
2) Choose grades.
3) Choose sizes.
Identification Code
Special type
Back supported type and Press fit type are available.
Press Fit Design Die Blank （WD960/WD970）
WD960,WD970 type adopt original design which PCD is pressed into support ring after sintering to avoid horizontal crack while machining.
Back Supported Design Die Blank （WD915MW/WD920MW）
Back Supported die can reduce the risk of horizontal crack on drawing hard wire.
