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Which of the following has more strength? CR-V (Chrome Vanadium) or those tools that are black colour! I don't know what they are made of! They are just black. Something like this:

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It isn't shiny like a CR-V tool:

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Which of the above tools can withstand higher torque values?

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    Who knows? You're question is too broad because manufacturing techniques between brands is not the same. It also depends on what you us them for and how you use them. Sep 16, 2021 at 11:29
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    See capritools.com/…
    – HandyHowie
    Sep 16, 2021 at 11:53
  • It depends on what strength you are measuring, typically non-impact sockets are more resistant to deformation than impact sockets but are far more brittle - hence their unsuitability for impact gun applications.
    – Mauro
    Sep 16, 2021 at 11:55
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    @Mauro I shattered a "standard" non-impact socket (a good quality one) on a seized wheel nut... I now have an impact rated socket - no problem with that so far...
    – Solar Mike
    Sep 16, 2021 at 12:57
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    @NarimanAsgharian Your concerns are unfounded. Especially for removing bolts in steel. Really no problem. Should it happen, in some rare cases, the bolt is that stuck, there are damages in any way, with or without impact gun.
    – Martin
    Sep 17, 2021 at 13:08

3 Answers 3

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The matte black coated ones are impact sockets: They are supposed to resist the forces from a impact gun. They are heavier and thicker than the chrome coated ones.

The chrome coated ones are suited for manual wrenching: They have thin walls, so you can fit them in places where the thick ones won't enter. They can break when used with an impact tool. That doesn't mean that they are worse than the impact sockets. They have their scope and, assuming decent quality and no abuse, will hold for a lifetime.

The "chrome vanadium" engraving is a bit deceiving: Those alloy metalls are expensive and you will have no warranty that the tool contains just the right amount of them. Tools from good brands are made well and have no need to display the "chrome vanadium" seal. Bad tools are prone to have falsified descriptions, especially regarding their content of alloys. In either case there is no need to know the alloy. So, ignore the "chrome vanadium" inscription and focus one better quality indicators.

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If those black sockets are the quality ones meant for impact guns then they are rated higher.

However if they are a cheap chinesium copy they may not be strong at all.

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    Chinesium is my word of the week!
    – GdD
    Sep 16, 2021 at 13:02
  • @GdD aka "use once and throw away"...
    – Solar Mike
    Sep 16, 2021 at 13:03
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Basically PR, the black looks stronger. Strength depends on: hardness, thickness, reducing any notches (that can cause stress concentrations). Chrome or black finish has only psychological affects. The vanadium is also PR, it sounds more exotic than chrome or molybdenum , which are the primary alloy elements in most tools. Alloys are added for hardenability; in varying amounts one can alloy with several different elements and get the same hardenability = tool strength. Vanadium makes more stable carbide than most elements so is good to preserve cutting edges in knives, shears, etc. V is also used in lower amounts because it does make vary stable carbides and then contributes less to hardenability.

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  • I once had a chinesium 1/4 drive socket set; carbon steel, no alloy ,soft as brass. But I outsmarted them ; carburized about 10 thousands and quenched from high temperature . They were OK after that, never as good as Cr Mo. Sep 16, 2021 at 16:12
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    I know of no restrictions on tools being imported to US. Sep 16, 2021 at 19:24
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    @NarimanAsgharian you've never seen "made in China"? and generally you are allowed to import anything you want as long as it's not dangerous.
    – user253751
    Sep 17, 2021 at 8:22
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    @NarimanAsgharian don't overestimate how much money the average American person has... it might be worth more than Chinese money but also everything costs more. (I am not American)
    – user253751
    Sep 17, 2021 at 9:02
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    @NarimanAsgharian there's also a valid case (in the US, western Europe etc.) for cheap tools that you expect to use once or twice, or only expect light duty uses. For example some big sockets are used in bicycle maintenance - but you only need to do up to 40Nm with a 24mm socket. My socket set is cheap, bought for fairly minor car stuff and DIY but still overkill for that sort of application.
    – Chris H
    Sep 17, 2021 at 12:31

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