Yeah I know but I’m hitting post anyway




The first day of spring brought snow so I’ve retreated from the still cold slab of my garage floor, to thoughts of my next N14 engine build, and what kinds of materials I might want.


In particular I would like to see more top grade Powdered metal options. And the main reason for writing this is the biggest problem with powdered metals..... the word powdered. Forged is a word that brings to mind fiery volcanoes and the god Vulcan hammering away how can there ever be anything better than that. Well I will always have a place for hand hammered Damascus tool blades, I have been won over by an Elmax powdered metal tool steel blade that just does things no other metal Ive used can. And powdered metal has proven itself in OEM connecting rods for quite a few years now.


So what is powdered metal and how does it do its thing? Well I’m not going to pretend to be an expert so read all you can. This is my take on the stuff though. The first thing to consider is that metals are not homogenous even if I was taught they were back in school, but have a lot of variation in there structure. Powdered metals are able to get a more ideal distribution of alloying elements in the mix which allows more of the ideal potential to be unlocked, and allows the metal to be more purpose tuned. Its maybe like having a stack of lumber made mostly of the one mostly clear extra heavy board instead a greater variety like we usually see. Of coarse the thing is that because powdered metals are so tunable there is a huge difference in a cheap gear made for a kitchen appliance and what I want which is a step or two above the OEM connecting rods.


The end result is that I think that we could get lighter and more rigid components without losing the bullet proof toughness we need or having to go broke to get them. But we need to ask for the next level tech even when buying the current offerings so our suppliers know there is a market.

 

Isn't that also called "sintered metal"?

http://en.wikipedia.org/wiki/Sintering
It's been around for a while. Some results are better than others.

 

Yeah, its sintered Metal. It has different properties depending on what its used for.

Its used primarily for its porous properties.

Per the wiki,

Advantages
Particular advantages of the powder technology include:

Very high levels of purity and uniformity in starting materials
Preservation of purity, due to the simpler subsequent fabrication process (fewer steps) that it makes possible
Stabilization of the details of repetitive operations, by control of grain size during the input stages
Absence of binding contact between segregated powder particles – or "inclusions" (called stringering) – as often occurs in melting processes
No deformation needed to produce directional elongation of grains
Capability to produce materials of controlled, uniform porosity.
Capability to produce nearly net-shaped objects.
Capability to produce materials which cannot be produced by any other technology.
Capability to fabricate high-strength material like turbine blades.
After sintering the mechanical strength to handling becomes higher.
The literature contains many references on sintering dissimilar materials to produce solid/solid-phase compounds or solid/melt mixtures at the processing stage. Almost any substance can be obtained in powder form, through either chemical, mechanical or physical processes, so basically any material can be obtained through sintering. When pure elements are sintered, the leftover powder is still pure, so it can be recycled.

Disadvantages
Particular disadvantages of the powder technology include:

100% sintered (iron ore) can not be charged in the blast furnace.
By sintering one cannot create uniform sizes.

 

I was under the impression that OEMs use powered metals because they are stronger than cast and require very little machining after they are pressed unlike forgings which require reworking and heat treating, etc. which make them more expensive.

But if you are building a one-off engine this cost savings is small and is really irrelevant. I'd go with metals pulled straight from Mt. Doom itself.

 

from my understanding...yup..very similar...
commonly used...heck many part of the gen1 cooper used it...but the parts were not strong enough to for the SC motors....so forged items were used...
unfortunately to cut costs engine makers are used cheaper and cheaper process often using parts that are "just good enough".....leaving little or zero margin for folks to increase performance......

 

Its more of a risk vs. reward. In the automotive industry its all about striking a balance to the breaking point.

Cost is a consideration
Fuel efficient (read: weight) is a consideration
Toughness (how long it will last)

You can't have all of those without sacrificing one or the other. If you made everything in this car out of forged titanium, it would be tough and light as hell, but not affordable. If they only sold 1 Mini like this, they couldn't pay for R&D and therefore would be unprofitable.

Really common subject for anyone who designs or works on them. Mechanics always ask why engineers build the car so they can't work on them. Customers ask why they can't drive a Cadillac for the price of a Cavalier. Everyone wants a 20 year warranty, and when it goes out of warranty, they complain its not covered. Or the part should never break....

People are just unrealistic.

 

They want their motor to be 500 HP, last for 500 thousand miles, and cost $500. Something an old shop buddy used to say.

 

Higher end powdered metals need more steps and can be super high quality. the tool steel I have is super fine grained and has excellent density I actually use a microscope sometimes to fine tune my sharpening, on oem rods you can see the grain structure on the caps fracture points its clearly a step below what can be done. Heat treating on powdered metals seems to produce a greater range of effects and is often a rebaranding point in some uses. Cost wise its always funny to see volume runs get short changed over small differences because the numbers add up and seem significant the question is are the bean counters or enthusiast making the calls. Trade off wise that's the thing that has me writing hoping to get more interest. usually in steels I see that I cant have a hard tough and machinable material but now it seems I can, I just need Gandalf to conjure some for the enthusiast crowd so we can go slay some Mustangs and chase lotus in our Mini's.