Question For Metalurgist

[shortbarrel]

I was restoring a modern rifle and had to silver braze the finger part I made to the upper part of the broken trigger. It was some kind of casting or powder metal.  When I attempted to file the broken part, it was harder than the file, so I went to the disc sander to true it up. The heat from grinding made the part ooze oil. Heated it red hot and burned the oil out and it brazed fine.It annealed in the process enough to be filed. My question is, why could this process not be used in making locks,set triggers,and etc. I have machined oilite bearings and powder metal bearing housings,but both were soft. Could Bob Roller or some other folks on this site answer my question. What kind of metal is this, i have never encountered it before.         

[Captchee]

 Im just guessing here but  it could have been a MIM (Metal injection molding)  part.
 But I don’t know if one could silver solder such a part ??  I guess it could be possible since it’s a powdered metal . But I just don’t know .
 I can tell you the process makes very strong parts . To the point there has even been  test to make barrels from the same process .
 But then we are getting into an area that’s  not part of what we do here  so ill stop at that .
Bob maybe able to shed more light on  it 

[Bob Roller]

I have no real idea as to this trigger or who made it. Years ago there
were some lock parts made by casting them from a material normally
unique to turbines in jet aircraft engines and I had a few of them,mostly
lock plates that shattered like glass when an attempt was made to straighten them.
I just replaced a hammer on a pristine lock I made for a Hawken in 1982 and it was
also glass hard and broke when the builder tried to flex it to one side.
I have a few Thompson-Center Seneca hammers that are also this hard.These are
left over from a German target pistol project in the late 70's and early 80's.
Maybe Jim Kelly can tell you what you were dealing with.

Bob Roller