What is the sintered metal of the post-64 Win 94s?

[Tycer]

What's your best description?

What are the problems?

What years were affected?

[Chuck 100 yd]

Good question. I have heard it is metal alloy that is in powdered form and pressed into a form (die) and heated to very high temp. Similar to forging but not exactly the same. Many other parts are made that way today. All the gears in lawn equipment are cintered metal and are quite tough.
I am sure someone will chime in with the accurate poop on this.

Here is a link for more on powdered metal parts.
http://www.thomasnet.com/about/powdered ... 66008.html
BTT

[MacEntyre]

How does the Powdered Metal Process Work?
Powdered Metal Parts
http://www.cypressindustrial.com/powder ... _work.html

There are several steps involved in how the powdered metal process works. Similar to investment casting there are several steps, but the end result can be a low-cost, high-quality powdered metal part, also called metal injection molding (MIM). Listed below is the typical sintered metal casting process in order:

Blending - This is the process of combining metal powders or alloys together with lubricants to produce a homogeneous mix.

Briquetting - This process is where metal powders or alloys are compressed while restricted in a die, at pressures as low as 10 to 45 tons per square inch.

Sintering - Here each individual particle bonds into a mass. The parts are heated in a protective atmosphere furnace to a high relative temperature below the melting point of the particular metal or alloy.

Repressing - This is the final pressing of a sintered metal part to obtain proper size and physical properties.

Infiltrating - This process of fills the pores of a sintered metal part with a metal or alloy of a lower melting point.

Impregnation - This process fills the pores of a sintered metal part with a lubricant.

Heat Treating - This is the heating of a sintered metal part in a protective atmosphere and then oil quenching the part. The results are usually improved strength and hardness.

Machining - If required powdered metal parts can be machined to obtain the desired shape before or after heat-treating is completed.

[Hobie]

As I understand it, they were formed using an early type of Metal Injection Molding (MIM) process not exactly sintered steel as I understand the term. For bluing the receiver had to be plated with a ferrous alloy.

They seem to actually hold up pretty well even if they are ugly as sin.

[Griff]

What's your best description?

Answered above.

What are the problems?

Requires a special "bluing" process. Other'n that, not a durn thing.

What years were affected?

1964 - 1981 approx.