What's happened to this ratchet?

[German Satin]

Below is a pic of a Halfords (basic, not 'advanced') 3/8 ratchet. There appears to be a curved shaped crack in square drive. I've jabbed at it with various things to see if just shears off in a chunk but it's still ok. So, this is a cheap (but really nice quality for what it is) ratchet so I won't be gutted if it fails ... long story short I think the entire gear is cast from powdered metal because I can't see any machining marks on it. This type of manufacture can run into many issues, cracking being just one of them.
Would appreciate any replies from anyone who knows about powdered metal stuff ...

 

[sweet victory]

Looks like a classic illustration of failure via torsion for brittle materials. Reference right side diagram below for representation. Pretty sure that anvil is not powdered metal, I can see turning marks near the faceplate.

 

[JradM]

Interesting failure. I would expect the gear to slip before the square-drive cracked from torsion overload. Could have been some sort of defect in the metal though I suppose. You've not be using the ratchet as a hammer I trust? Don't start now either.

 

[four.cycle]

^ I would submit that sweet victory's answer above is correct. I have seen more than a few inexplicable failures on new hand tools similar to what you have there.

 

[German Satin]

Interesting observations ... I'm no metallurgist but when I see a crack like that in the business end of a ratchet it doesn't inspire confidence. I haven't abused the ratchet, rather I think the defect has been there hiding under the black finish from the start. Think I will get rid or just use and see what happens. Thanks again for your input, always nice to read what other members think.

 

[four.cycle]

This has been discussed in another thread somewhere here, but:

In the "warranty" returns we got back at the warehouse, there were invariably pieces that had literally "exploded" the first time any torque was applied. Generally it was sockets. Sometimes half the jaw of an open-end wrench would snap off.
Nothing is perfect. Flaws occur in metal working.
The only way to prevent failures of that nature would be to load-test every single piece coming down a production line, which simply isn't feasible when you're talking about a production facility that is stamping out thousands of units daily.
That same company stamped out hundreds, if not thousands, of that exact same ratchet on that exact same day, and most of them are still in service.
You were the lucky guy that got the cherry. Happens to all of us now and then.

 

[Al Borland]

Case-hardened?