Material inspection
Material inspection
Material inspection
Screening at the raw material stage is what keeps problems from appearing after machining.
Screening at the raw material stage is what keeps problems from appearing after machining.
Screening at the raw material stage is what keeps problems from appearing after machining.
OVERVIEW
The purity of tungsten on the market ranges from 99.75% to 99.99%. Korea Tungsten uses raw material of even, consistent quality to secure product life and deposition quality.
The purity of tungsten on the market ranges from 99.75% to 99.99%. Korea Tungsten uses raw material of even, consistent quality to secure product life and deposition quality.
The purity of tungsten on the market ranges from 99.75% to 99.99%. Korea Tungsten uses raw material of even, consistent quality to secure product life and deposition quality.
Crack inspection at the raw material stage screens out cracks. Tungsten is brittle, and a micro-crack left in the raw material leads to breakage during machining.
Crack inspection at the raw material stage screens out cracks. Tungsten is brittle, and a micro-crack left in the raw material leads to breakage during machining.
Crack inspection at the raw material stage screens out cracks. Tungsten is brittle, and a micro-crack left in the raw material leads to breakage during machining.
Material selection criteria
Tungsten and molybdenum are refractory metals, and their physical and mechanical properties differ entirely from ordinary steel and non-ferrous metals. These are the criteria we check when choosing a material at the machining design stage.
Tungsten and molybdenum are refractory metals, and their physical and mechanical properties differ entirely from ordinary steel and non-ferrous metals. These are the criteria we check when choosing a material at the machining design stage.
Tungsten and molybdenum are refractory metals, and their physical and mechanical properties differ entirely from ordinary steel and non-ferrous metals. These are the criteria we check when choosing a material at the machining design stage.
01
01
MELTING POINT
MELTING POINT
Service temperature and melting point
Service temperature and melting point
Tungsten has the highest melting point of any metal in existence at 3,422℃. Molybdenum is lower at 2,623℃ but keeps excellent strength in the 1,000–1,500℃ range.
02
02
DBTT
DBTT
Machinability and ductile-to-brittle transition temperature
Machinability and ductile-to-brittle transition temperature
Both materials are strongly brittle at room temperature and prone to micro-cracking. Tungsten has a higher DBTT than molybdenum, so sharp corners have to be avoided and generous radii allowed.
03
03
THERMAL CONDUCTIVITY
THERMAL CONDUCTIVITY
Density and thermal conductivity
Density and thermal conductivity
Both have low thermal expansion coefficients and excellent dimensional stability. Where high density is needed tungsten fits; where weight efficiency matters molybdenum does.
04
04
GAS & ACID REACTION
GAS & ACID REACTION
Chemical corrosion resistance
Chemical corrosion resistance
They oxidize rapidly in air above 400–500℃, so the design assumes use in a vacuum or a reducing atmosphere.
05
05
GRADE SELECTION
GRADE SELECTION
Stock form for the machining method
Stock form for the machining method
Pure grades are chosen for semiconductor and electrode processes that need high purity; doped and alloyed grades when machinability or the recrystallization temperature has to be raised.
01
Service temperature and melting point
MELTING POINT
Tungsten has the highest melting point of any metal in existence at 3,422℃. Molybdenum is lower at 2,623℃ but keeps excellent strength in the 1,000–1,500℃ range.
02
Machinability and ductile-to-brittle transition temperature
DBTT
03
Density and thermal conductivity
THERMAL CONDUCTIVITY
04
Chemical corrosion resistance
GAS & ACID REACTION
05
Stock form for the machining method
GRADE SELECTION
※ Material cost is high, so making the most of standard sizes in the initial design to reduce the amount cut away is the key to cost reduction.
※ Material cost is high, so making the most of standard sizes in the initial design to reduce the amount cut away is the key to cost reduction.
※ Material cost is high, so making the most of standard sizes in the initial design to reduce the amount cut away is the key to cost reduction.
EQUIPMENT
Inspection equipment
The measuring and testing equipment used in incoming inspection.
The measuring and testing equipment used in incoming inspection.
The measuring and testing equipment used in incoming inspection.
Micrometer
Micrometer
Micrometer
Precision optical microscope
Precision optical microscope
Precision optical microscope
Hardness tester
Hardness tester
Hardness tester
Vernier calipers
Vernier calipers
Vernier calipers
PURITY
Purity and density
Purity is defined as a specific figure. Alongside overall purity, we check whether there is a limit on the content of a particular element.
Purity is defined as a specific figure. Alongside overall purity, we check whether there is a limit on the content of a particular element.
Purity is defined as a specific figure. Alongside overall purity, we check whether there is a limit on the content of a particular element.
3N
3N
3N
99.9%
99.9%
99.9%
4N
4N
4N
99.99%
99.99%
99.99%
5N
5N
5N
99.999% and above
99.999% and above
99.999% and above
Impurity content
Oxygen, nitrogen and carbon content have a large effect on the brittleness of tungsten. For semiconductor targets, radioactive element content has to be extremely low.
Oxygen, nitrogen and carbon content have a large effect on the brittleness of tungsten. For semiconductor targets, radioactive element content has to be extremely low.
Density and grain structure
We check how close it comes to the theoretical density of 19.28 g/cm³. In sintered products, the higher the relative density and the finer and more uniform the grain, the better the machinability and the more consistent the wear.
We check how close it comes to the theoretical density of 19.28 g/cm³. In sintered products, the higher the relative density and the finer and more uniform the grain, the better the machinability and the more consistent the wear.
※ Purity can be verified from the certificate of analysis (COA), the per-lot chemical composition report. We also check which instrument it was measured on — GDMS, ICP-MS or another.
※ Purity can be verified from the certificate of analysis (COA), the per-lot chemical composition report. We also check which instrument it was measured on — GDMS, ICP-MS or another.
※ Purity can be verified from the certificate of analysis (COA), the per-lot chemical composition report. We also check which instrument it was measured on — GDMS, ICP-MS or another.
SCOPE
Scope
01
01
Refractory metals such as W · Mo · Ta
Refractory metals such as W · Mo · Ta
Refractory metals such as W · Mo · Ta
We machine from raw material of even, consistent quality.
We machine from raw material of even, consistent quality.
We machine from raw material of even, consistent quality.
02
02
Purity verification
Purity verification
Purity verification
We verify the purity of incoming material.
We verify the purity of incoming material.
We verify the purity of incoming material.
03
03
Crack inspection at the raw material stage
Crack inspection at the raw material stage
Crack inspection at the raw material stage
Incoming raw material goes through crack inspection to screen out micro-cracks.
Incoming raw material goes through crack inspection to screen out micro-cracks.
Incoming raw material goes through crack inspection to screen out micro-cracks.
04
04
Cut after confirming the requested specification
Cut after confirming the requested specification
Cut after confirming the requested specification
We check the material specification and the accompanying documents, then cut to the specification you requested.
We check the material specification and the accompanying documents, then cut to the specification you requested.
We check the material specification and the accompanying documents, then cut to the specification you requested.
05
05
Material traceability
Material traceability
Material traceability
We record which material a part was made from.
We record which material a part was made from.
We record which material a part was made from.
※ Where purity or composition testing is required, we commission an accredited testing laboratory and hand over the resulting report with the parts.
※ Where purity or composition testing is required, we commission an accredited testing laboratory and hand over the resulting report with the parts.
※ Where purity or composition testing is required, we commission an accredited testing laboratory and hand over the resulting report with the parts.
Advanced material supply and machining,
a global material leader
From raw material to finished part, the best solution seen from your side.
Weekdays 9:00 AM – 5:30 PM (alternate Fridays until 4:00 PM; closed weekends and public holidays)
Advanced material supply and machining,
a global material leader
From raw material to finished part, the best solution seen from your side.
Weekdays 9:00 AM – 5:30 PM (alternate Fridays until 4:00 PM; closed weekends and public holidays)
KOREA TUNGSTEN CO.,LTD
KOREA TUNGSTEN CO.,LTD
Refractory metal supply and ultra-precision machining — core materials for semiconductor, display, defense, space, medical & radiation.
INNOMT LLC
INNOMT CO.,LTD
Korea Tungsten's official overseas division
Key industries served
Customer support
© 2026 Korea Tungsten Co., Ltd. All rights reserved. 83 Bideukbawi-gil, Jori-eup, Paju-si, Gyeonggi-do 10949, Korea (364-2 Osan-ri) +82-31-975-1717
© 2026 INNOMT Co., Ltd. All rights reserved. Unit A-1710, IS Biz Tower Hangang 3, 50 Eutteum-ro, Deogyang-gu, Goyang-si, Gyeonggi-do 10543, Korea +82-2-6408-4239
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KOREA TUNGSTEN CO.,LTD
KOREA TUNGSTEN CO.,LTD
Refractory metal supply and ultra-precision machining — core materials for semiconductor, display, defense, space, medical & radiation.
INNOMT LLC
INNOMT CO.,LTD
Korea Tungsten's official overseas division
Key industries served
Customer support
© 2026 Korea Tungsten Co., Ltd. All rights reserved. 83 Bideukbawi-gil, Jori-eup, Paju-si, Gyeonggi-do 10949, Korea (364-2 Osan-ri) +82-31-975-1717
© 2026 INNOMT Co., Ltd. All rights reserved. Unit A-1710, IS Biz Tower Hangang 3, 50 Eutteum-ro, Deogyang-gu, Goyang-si, Gyeonggi-do 10543, Korea +82-2-6408-4239
Privacy Policy
Terms of Use
Cookie settings
KOREA TUNGSTEN CO.,LTD
KOREA TUNGSTEN CO.,LTD
Refractory metal supply and ultra-precision machining — core materials for semiconductor, display, defense, space, medical & radiation.
INNOMT LLC
INNOMT CO.,LTD
Korea Tungsten's official overseas division
Key industries served
Customer support
© 2026 Korea Tungsten Co., Ltd. All rights reserved. 83 Bideukbawi-gil, Jori-eup, Paju-si, Gyeonggi-do 10949, Korea (364-2 Osan-ri) +82-31-975-1717
© 2026 INNOMT Co., Ltd. All rights reserved. Unit A-1710, IS Biz Tower Hangang 3, 50 Eutteum-ro, Deogyang-gu, Goyang-si, Gyeonggi-do 10543, Korea +82-2-6408-4239
Privacy Policy
Terms of Use
Cookie settings