It can be hard to distinguish between scrap carbide and high-speed steel [HSS] by simply looking at the two, but the differences between the two alloys (and if you don’t know what an alloy is, take a listen here) are significant and could mean more money in you pocket depending on which one you have.
Differences In Chemical Makeup
Right off the bat, you have to realize the price difference and say to yourself, “Why is carbide so much more valuable than normal HSS (High-Speed Steel)?” Let’s go over a few significant differences in the chemical composition to give you a better overall idea.
High-Speed Steel | Carbide | |
Tungsten | 1-18% | 60-90% |
Iron | At least 70% | 0-4% |
Carbon | 1-7% | 0-3% |
Chromium | 1-7% | – |
Vanadium | 0-2% | – |
Molybdenum | 0-4% | – |
Magnetic? | Strong pull | Slight pull |
The most significant difference that you can see is the tungsten vs. iron makeup. The value of iron is drastically lower due to iron being so much more abundant across the world commodity focus.
Differences In Applications
While both are used inside the machine shop world, they are very different for a few reasons.
- Carbide bits and drills are used for their longevity and sharpness.
- Carbide or tungsten-based units will last much longer and generally give you a more precise cut while using CNC machines, machine tools that cut or move material as programmed on the controller, or other drilling machines.
- While more expensive, you will generally get a longer lifespan out of carbide bits compared to others.
- Higher cutting speed means they can go faster and absorb more heat.
HSS is used as a substitute for carbide in many applications.
- Price: these bits are much cheaper than carbide, and you can buy many of these bits to replace one carbide bit.
- Size of the job: if you or a machine operator are using these bits for smaller batches, then it may not be worth it to have carbide tips.
- Great alternative: HSS is a great option compared to carbide, and in shops that are using multiple tools, this will prove significantly cost beneficial.
Suggested Reading: Metal of the Month: Carbide
Differences In Scrap Value
Carbide bits are generally worth 10-30 times that of HSS counterparts. These bits have metal tungsten, which is not only expensive but also much rarer and harder to work with than high-speed steel. Because of carbides’ large proportion of tungsten in its makeup, the refining process is also much more manageable. Believe it or not, many scrap pieces of carbide are ground up into a powder before getting melted and made into new units.
HSS contains much lower amounts (if any) of tungsten and will be worth considerably less per pound. These items typically have a value of 20-100% more than regular steel. Sometimes scrap yards do not want to waste their time with HSS because there are so many different grades. With varying grades of HSS readily available, it is challenging for a scrap yard to warrant separating every drill bit. Many yards will only buy as regular prepared steel.