Hard Chrome

N

Natlek

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Jun 9, 2015
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Hard chrome, also known as industrial chrome or engineered chrome, is used to reduce friction, improve durability through abrasion tolerance and wear resistance in general, minimize galling or seizing of parts, expand chemical inertness to include a broader set of conditions (especially oxidation resistance, arguably its most famous quality), and bulking material for worn parts to restore their original dimensions.[5] It is very hard, measuring between 65 to 69 HRC. Hard chrome tends to be thicker than decorative chrome, with standard thicknesses in nonsalvage applications ranging from 0.2 to 0.6 mm (200 to 600 µm), but it can be an order of magnitude thicker for extreme wear resistance requirements, in such cases 1 mm (1,000 µm) or thicker provides optimal results.
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Why is not used on custom knives? There are so many advantages especially when used on Carbon steels? And there is nothing more beautiful than sandblasted and then hard chrome knives ?
 
That's a very good question!
Puma used it on quite a few knives.
Industrial hard chrome would hold up worlds better than paint (Duracoat and Ceracote are paints,) or bluing. I have suggested it several times on the shop talk forum, but it seems to go over their heads.
 
I do not know what it costs in the United States .But here cost about 7-8 euro for 10x10 centimeters /about 4x4 inch/ surfaces . Does not look too expensive ? I have made a knife from 52100 and hard chrome it ... I am very pleased with the result .

before

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after , but the picture is not shows how nice looks finis ...

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The hard chrome would probably be better for only the body of the blade, it is very easy to chip out at sharp corners such as a knife edge. We used to use it all the time in the large machine shop I worked in during my apprenticeship. Mostly for build-up after machining down worn bearing journals. Often it would be layered on nearly 1/16" thick, then ground back to finish size. One of the reasons it isn't often used for one-off custom blades is the cost for a small part is usually a little high. Best route to get reasonable pricing would be to send a batch of blades in I think.
 
A couple of thoughts :

Chroming tends to be environmentally detrimental so the cost of doing it by the book has moved it out of the US and or consolidated it into major cities. It seems like local places have dried up around here anyway and when I moved here there were several places doing it.

Secondly chroming can cause hydrogen embrittlement in alloy steel so if a knife was flexed and used hard it might crack. This shows up more, in my world anyway, in thin wall chromolly tubular structures cracking where if they had not been chromed they more than likely would have had a longer life or never broken ever. For instance unchromed items in steel last easily for thirty years of daily use where as the same structure in aluminum OFTEN fails in five years or so. We think of the aluminum as having a finite life (fatigue limit) and the chromolly as having an "infinite" fatigue limit. Chrome the same steel structure and . . . well . . . they break . . . somewhere . . . eventually.
 
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I've never heard of it causing steel to rust any worse than normal in any of the industrial items we made and repaired. The hydrogen embrittlement is a definite issue, forgot about that. The item being plated basically needs to go straight into an oven immediately after plating and get baked at about 375°F (190°C) to prevent this. Shotpeening the surface also can help. This is mostly done by the chrome shop that does the plating if the item would be at risk - this also would add to the cost.
 
For that matter, why not nickel plate it instead. Fewer steps and pretty easy to do in the home workshop. I actually did plate a small carbon steel knife years ago, but never used it.
 
Strider did an older run of Hard Chrome blades. Never had one though..
 
eKretz said:
I've never heard of it causing steel to rust any worse than normal in any of the industrial items we made and repaired. The hydrogen embrittlement is a definite issue, forgot about that. The item being plated basically needs to go straight into an oven immediately after plating and get baked at about 375°F (190°C) to prevent this. Shotpeening the surface also can help. This is mostly done by the chrome shop that does the plating if the item would be at risk - this also would add to the cost.
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I have no idea what you're talking?
Hard Chrome is classed as a "COLD" process, the operating temperature of 50 - 60°C ensures no detrimental effects to the physical or mechanical properties of the base materials
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Here we a talk about HardChrome plating ................ Not about decorative chrome plating on plastic :) it will last on knive forever , it will not chip, flake, crack, peel or separate from the base material even under the most rugged conditions

High Hardness
Electro-deposited Chrome is extremely hard, with typical values of 850 - 1050 HV (63 - 70 HRc), hence the term "Hard" Chrome. This makes it an excellent coating for wear resistant and abrasion resistant applications such as Moulds and Dies, Punches, Bearing and Seal surfaces, and sliding components.
Low Coefficient of fricton
Hard Chrome has a very low coefficient of friction, approx. one half that of Steel. The coefficient against Steel of 0.16 lubricated (0.21 dry), makes it ideally suited for such applications as Bearing and Seal surfaces, and machinery components.
Wear Resistance
The high hardness and low frictional properties of Hard Chrome provide it with extremely good resistance to abrasive and erosive wear, extending the life of components such as Moulds, Dies and Punches etc, up to ten times in most cases.
Corrosion Resistance
Hard Chrome has an extremely high resistance to atmospheric oxidation, and a good resistance to most oxidising and reducing agents.(with the exception to Chlorides and other Halides), hence its wide-spread use in the Food and Chemical Industries.
Sacrificial Wear Layer
Since Hard Chrome deposits are readily removed with chemical strippers, without detrimental effect to the base material, the part can be stripped and re-plated repeatedly, when wear shows, without loss or damage to the base part. This is a significant advantage for high wear, high cost parts such as Plastic Moulds and Dies where abrasive filled plastics are used.
Machining
Hard Chrome deposits can be successfully finished by grinding, linishing or polishing.
Applications
Hydraulic and Pneumatic Piston Rods and Cylinders
Plastic and Rubber Rolls, Moulds, Dies, Screws, etc.
Automotive and Mechanical components
Press Tools and Punches
Print Cylinders and Plates
Food Machinery
Valves, Gates and Bodies
Mining Equipment
Timber and Paper Processing Equipment
Pump Shafts and Rotors
Textile Components
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