What Metal Is Widia? Here's What to Know
For most people, the name Widia has no meaning. But not for those who work every day with precision drilling, complex cutting and machining on highly resistant materials. In fact, Widia is the trade name for an irresistible combination for making drilling and cutting tools that are particularly useful for demanding and stressful work.
Having quality tools for drilling hard metal, such as stainless steel, is a must for those involved in professional machining. In many cases, a good drill bit for metal in HSS, in cobalt or with titanium nitride coating is sufficient.
Those who need to work on other operational fronts - such as CNC milling or reaming, but also turning and tapping - must always aim high. For example on the Widia side. Let's discover more about this useful material.
What is Widia Material, Definition
Widia is a trademark registered by Friedrich Krupp AG on December 25, 1927 and attributed to an extremely resistant material, not found in nature but the result of specific processing. In fact, this alloy is born from a sintering and heat treatment process that unites fine powders of carbides and metals at temperatures of 1400 - 1500°C under pressure.
Also known as cemented carbide or hard metal, Widia owes its name to the German wie Diamant - hard as diamond - and is composed of tungsten carbide, titanium and tantalum in a percentage that varies from 80% to 95% in a cobalt metal base. All this allows Widia to be harder than high-speed steel and super high-speed steel (data source on Wikipedia). Here is a summary of the properties:
| Value | Relevance | |
|---|---|---|
| Melting point | 2870°C | Exceptionally high |
| Density | 14.5 g/cm³ (10% Co) | 2x iron (7.8 g/cm³) |
| Compression resistance | 6000 MPa | Excellent for tools |
| Elastic modulus | ~600 GPa | Stiffness superior to steel |
A curiosity: if someone asks the difference between Widia and hard metal, don't fall into the trap: there is none. In fact, they are just two ways of understanding the same thing. Widia is only the trade name for this alloy developed, as mentioned, by the German company Krupp.
What Are the Main Uses of Widia?
Cemented carbide - an alternative and symbolic name given to this alloy - is mainly used to make drilling and cutting tools such as lathe inserts, drill bits, circular saw blades and mills. This is necessary when looking for above-average performance given Widia's ability to machine hard materials while keeping the cutting edge sharp longer.
At least compared to steel tools. In fact, one of the essential characteristics of the material in question is the ability to last a very long time: cutting and drilling tools in Widia are more wear-resistant, so suitable for those who work every day with activities on hard materials like turning, reaming and boring. That is, activities that do not allow inaccuracies.
Technical Characteristics and Hardness
To understand the hardness of Widia, we must understand that it reaches HV 1500 HV while high-speed steel (HSS) stops at 1000. Diamond is the only material harder than Widia, but it is also phenomenal at high temperatures reached in intensive use: high-speed steel at 700°C loses about 85% of its hardness, hard metal reaches 45%.
Behavior at High Temperatures
| Temperature | Hardness Retained | Notes |
|---|---|---|
| Environment (20°C) | 1100-1900 HV | Maximum hardness |
| 700°C | ~85-90% original | Limited loss |
| 900-1000°C | ~60 HRC | 40-45% loss |
| 1000°C+ | Resists up to 1000°C in cutting | Operational |
Measurement Scales Used
| Scale | Typical Value | Full Range |
|---|---|---|
| Vickers (HV) | 1500 HV | 1100-1900 HV |
| Rockwell A (HRA) | 85-93 HRA | 90 HRA (with 10% Co) |
| Rockwell C (HRC) | 69-81 HRC | 66-69 HRC (some grades) |
| Mohs | ~9 Mohs | 8.5-9.5 Mohs |
Pros and Cons of This Hard Metal at Work
First and foremost, we must highlight the strengths and advantages for those using Widia. It is one of the hardest materials after diamond, making it perfect for working on resistant materials. We are talking about a hardness of approximately 1500 - 2000 HV (Vickers), values impossible for normal steels. Furthermore, tools in this category are essential for those working on assembly lines.
In fact, this choice allows you to reduce downtime for replacing bits and mills: Widia maintains the cutting edge longer than steels, even at high temperatures. This means fewer interruptions and maintenance, but also more productivity.
It must be remembered that, like all materials, Widia is not without problems. For example, if I use such a drill bit with excessive speed, in the absence of coolant and with an unusual technique - for example with percussion drilling on metal - there is a concrete risk of breaking the tool. In fact, Widia metal is resistant but brittle to impacts. Abrupt temperature changes can cause cracks. This is why a good cooling system is always needed during use. Then there are the prices to consider.
Attention: the values are high but this is not a superfluous expense for those who work every day with these activities. Widia tools are more expensive but the longer lifespan can make this choice more economical over time for intensive machining. Remember that there are wall drill bits in Widia but also for resistant metals.
