Why Two Suppliers' "YG6" Are Not the Same Material
· Vanguard Carbide
Grade names like YG6 or K20 describe a family or an application, not a specification. What that means when you compare quotations.
The Short Version
- A grade name tells you roughly what a carbide is for. It does not tell you what it is. Two parts stamped with the same grade name, from two producers, can differ in hardness, toughness and service life.
- This matters most when you are comparing quotations: a cheaper "YG6" is not necessarily the same material as a dearer one.
What The Chinese YG Names Actually Say
- In the Chinese naming system, YG denotes a straight tungsten carbide–cobalt grade and the number is the nominal cobalt percentage: YG6 is about 6% cobalt, YG8 about 8%.
- That is a binder content, not a full specification. Grain size, which has a large effect on hardness and toughness, is not in the name at all. Two YG6 grades with different grain sizes behave differently in the same job.
What The ISO Codes Actually Say
- ISO 513 classifies hard cutting materials by the workpiece they are intended to cut — P for steel, M for stainless, K for cast iron, N for non-ferrous, S for heat-resistant alloys, H for hardened material — with a number for the balance between wear resistance and toughness.
- It is an application grouping. "K20" means the producer intends the grade for a particular kind of work at a particular point on that scale. It is not a chemistry or a property specification, and two K20 grades are not interchangeable by definition.
Why We Do Not Publish A Generic Property Table
- We could put a table of hardness and transverse rupture strength on this site, and it would look reassuring. It would also be misleading, because the numbers that matter are the ones for the specific grade in your specific part.
- Instead we send the data sheet for the grade we propose, for the part we are quoting.
How To Compare Quotations Fairly
- Ask each supplier for the grade's own data sheet, not just the grade name.
- Compare binder content, grain size and the measured properties, not the label.
- Ask what the grade is normally used for. A grade that is excellent in one application can be the wrong choice a few millimetres away in the same assembly.