Content Menu
● Understanding Tungsten Carbide Hardness
● Materials That Can Scratch Tungsten Carbide
>> 1. Diamonds (Mohs 10)
>> 2. Silicon Carbide (Mohs 9.5)
>> 3. Tungsten Carbide Tools
>> 4. Aluminum Oxide (Mohs 9)
>> 5. Coating or Plating Weaknesses
● Factors Influencing Scratch Resistance
● Practical Implications for Jewelry Owners
>> Maintenance Tips
>> Limitations
● Conclusion
● FAQs
>> 1. Is tungsten carbide completely scratch-proof?
>> 2. Can everyday materials like keys or glass scratch tungsten carbide?
>> 3. How do I remove scratches from a tungsten ring?
>> 4. Is tungsten carbide more scratch-resistant than titanium?
>> 5. Does a brushed finish make scratches less noticeable?
● Citations:
Tungsten carbide is renowned for its exceptional hardness and durability, often marketed as "scratch-resistant" in jewelry and industrial applications. However, despite its Mohs hardness rating of 8–9, certain materials and conditions can indeed scratch or damage it. This article explores the science behind tungsten carbide's scratch resistance, identifies materials capable of scratching it, and provides practical advice for maintaining its finish.
Understanding Tungsten Carbide Hardness
Chemical Composition
Tungsten carbide (WC) is an alloy of tungsten and carbon atoms in a 1:1 ratio. Its extreme hardness stems from strong covalent bonds between tungsten and carbon atoms, creating a rigid lattice structure[1][8].
Mohs Hardness Scale
On the Mohs scale, which measures scratch resistance, tungsten carbide ranks between 8 and 9[2][4]. For comparison:
- Diamond: 10
- Silicon carbide: 9.5[3]
- Corundum (sapphire/ruby): 9
- Tungsten carbide: 8.5–9[8]
- Titanium: 6
Materials That Can Scratch Tungsten Carbide
1. Diamonds (Mohs 10)
Diamonds are the only natural material harder than tungsten carbide. Prolonged contact with diamond-tipped tools or jewelry can leave visible scratches[6][13].
2. Silicon Carbide (Mohs 9.5)
Widely used in abrasives and cutting tools, silicon carbide (SiC) surpasses tungsten carbide in hardness, making it capable of causing scratches[3].
3. Tungsten Carbide Tools
High-purity tungsten carbide tools, such as drill bits or grinding wheels, can scratch lower-grade tungsten carbide jewelry due to variations in alloy composition[1][9].
4. Aluminum Oxide (Mohs 9)
Common in sandpaper and industrial abrasives, aluminum oxide (corundum) can scratch tungsten carbide under sufficient pressure[1][6].
5. Coating or Plating Weaknesses
Colored or plated tungsten rings (e.g., black, gold) have a softer outer layer (often zirconium alloy) that scratches more easily, revealing the base metal beneath[2][8].
Factors Influencing Scratch Resistance
1. Alloy Composition
- Higher carbon content increases hardness but brittleness[1][9].
- Bind metals like cobalt or nickel reduce scratch resistance[1][22].
2. Surface Finish
- Brushed finishes may trap debris, mimicking scratches[4][21].
- Polished surfaces show scratches more readily[2][4].
3. Impact Force
Even softer materials like steel (Mohs 5) can cause chipping or pitting under high pressure[1][9].
Practical Implications for Jewelry Owners
Maintenance Tips
- Clean regularly with soapy water to remove residue mimicking scratches[2][6].
- Avoid wearing plated rings during manual labor[2][8].
- Use jewelry polishing cloths for superficial marks[2][13].
Limitations
- Cannot be resized due to brittleness[8][9].
- Shatters under extreme force instead of bending[18][22].
Conclusion
While tungsten carbide is among the hardest materials used in jewelry, it is not impervious to scratches. Diamonds, silicon carbide, and industrial abrasives can damage its surface, while plated coatings and manufacturing defects further reduce scratch resistance. Understanding these factors helps users maintain their rings' appearance and longevity.
FAQs
1. Is tungsten carbide completely scratch-proof?
No. Although highly scratch-resistant, diamonds, silicon carbide, and other tungsten carbide tools can scratch it[1][3][6].
2. Can everyday materials like keys or glass scratch tungsten carbide?
No. Materials softer than Mohs 8 (e.g., steel, glass) cannot scratch tungsten carbide[5][13].
3. How do I remove scratches from a tungsten ring?
Most marks are residue from softer materials and can be cleaned with soapy water. Deep scratches in plated rings usually require replacement[2][6].
4. Is tungsten carbide more scratch-resistant than titanium?
Yes. Tungsten carbide (Mohs 8–9) outperforms titanium (Mohs 6)[2][7].
5. Does a brushed finish make scratches less noticeable?
Yes. Brushed finishes hide minor abrasions better than polished surfaces[4][21].
Citations:
[1] https://www.reddit.com/r/askscience/comments/x1el6/i_have_a_ring_made_of_tungsten_carbide_it_has/
[2] https://newmanbands.com/do-tungsten-rings-scratch-easily/
[3] https://www.syalons.com/2024/07/08/silicon-carbide-vs-tungsten-carbide-wear-applications/
[4] http://www.titaniumkay.com/tungsten-rings/can-you-scratch-a-tungsten-ring/
[5] https://forums.windowscentral.com/threads/will-tungsten-rings-scratch-your-screen.397353/
[6] https://www.larsonjewelers.com/pages/does-tungsten-scratch
[7] https://www.happylaulea.com/blogs/articles/say-goodbye-to-scratches-the-best-rings-for-scratch-resistance-and-durability
[8] https://va-tungsten.co.za/pure-tungsten-vs-tungsten-carbide-whats-the-difference/
[9] https://www.findurings.com/blogs/blog/can-tungsten-rings-be-scratched
[10] https://www.larsonjewelers.com/pages/tungsten-rings-pros-cons-facts-myths
[11] https://northernroyal.com/pages/how-durable-are-tungsten-rings
[12] https://forums.windowscentral.com/threads/will-tungsten-rings-scratch-your-screen.397353/
[13] https://theartisanrings.com/pages/do-tungsten-rings-scratch-easily-what-to-know
[14] https://jewelrybyjohan.com/blogs/metals-and-materials/how-durable-is-tungsten
[15] https://tryhitched.com/blogs/hitched/about-tungsten-wedding-bands
[16] https://www.youtube.com/watch?v=A-prdcknwIA
[17] https://etrnl.com.au/blogs/news/everything-you-need-to-know-about-tungsten-rings
[18] https://www.tungstenrings.com/tungsten-carbide-rings-facts-fiction/
[19] https://jewelrybyjohan.com/en-de/blogs/metals-and-materials/the-pros-and-cons-of-tungsten-rings
[20] https://www.tungstenaffinity.com/Polished-Tungsten-Wedding-Ring-Band-p/sil-p.htm
[21] https://www.tungstenringsco.com/milwaukee-concave-brushed-scratch-resistant-tungsten-carbide-band-p-132.html
[22] https://forums.tripwireinteractive.com/index.php
[23] https://www.walmart.com/ip/Cat-Scratch-Tungsten-Carbide-Ring/5523577898
[24] https://northernroyal.com/pages/the-official-tungsten-ring-guide
[25] https://obsessionsj.com/products/7mm-tungsten-carbide-wedding-band-with-scratch-finish
[26] https://theartisanrings.com/blogs/news/what-is-tungsten-carbide-characteristics-of-tungsten-carbide-rings
[27] https://www.reddit.com/r/askscience/comments/x1el6/i_have_a_ring_made_of_tungsten_carbide_it_has/
[28] https://www.pricescope.com/community/threads/gold-plated-tungsten-carbide-scratch-resistant.154283/
