Casting and Forming

IN my view the Aluminum Silicone Alloy A332.0 Pressure die casted or gravity die casted will be the most suitable as it posses both strength and bearing qualities.

A cheap source will be the used diesel engine pistons.

The casting need to be heat treated first at 480 deg C for 4 to 6 hours and quenched in water then aged at 200 to 240 deg C for 8 hours.

The housing component should be anodised to make it weather proof both chromic acid and oxalic acid or mixed could be used to anodize the housing

JDonnelly03,

The key to your question is 5,000 to 8,000 a year. The strength is what ever you want or need, anything can be cast or formed. No Problem.

The design will dictate the cost. You want to look at it like as if you were going to crack an egg, pull it apart and get a complete part. That means if you have lips, overhangs, recess' arms or bars, you need to find a way to get them attached another way. Tooling cost can be as low as $3,000 and as high at $30-50,000 and more. All depends on the design. Cast Iron will work if you treat it and paint it, and you can't swing a dead cat without hitting a cast iron foundry in the US.

Powered metal is a good choice for a small simple part, tooling is 30 to 40K but the piece part price is less then $10 each and the part ofter does not need any machining.

Investment casting is good for that quantity, but size and shape will decide if that will work.

Sand Casting is good for Iron, steels and aluminum, and can make anything. no problem, but you will need to have all mating surfaces machined before it would be much use.

I think I've given you a place to start, I think you should decide on a shape, (keep is simple if you can) and consult a Manufacturing engineer.

Hope this helps some.

That depend on you design,but what about this,it can work in low temperature and very cheap.

ASTM A536-72, MIL-I-11466B(MR), ferritic, shock resistant parts

Component Wt. % C 3.6 - 3.8 Ce 0.005 - 0.2 Cr 0.03 - 0.07 Cu 0.15 - 1 Component Wt. % Fe 90.738 - 94.175 Mg 0.03 - 0.06 Mn 0.15 - 1 Mo 0.01 - 0.1 Component Wt. % Ni 0.05 - 0.2 P Max 0.03 S Max 0.002 Si 1.8 - 2.8

Material Notes:
Carbon represents the total carbon in the above composition. Cerium is an optional constituent in ductile iron. Most ductile irons are specified based on mechanical properties and have loosely defined compositions. For example, 60-40-18 ductile iron is specified to have a minimum tensile strength of 60 ksi (414 MPa), a yield strength of 40 ksi (276 MPa) and an elongation of 18%. Ferritic, may be annealed. Applications include shock resistant parts, low temperature service, machine components subject to shock and fatigue loads.

I agree with LABYGUY on all points except the investment casting. Unless your housing is very complex then investment casting will be too slow and costly. Die cast is a good choice for those quantities as long as the housing won't have to take an abnormal amount of abuse. If it is a simple enough design then machining may be the way to go especially if done by a shop that knows HSM (high speed machining) tecniques. This would save a lot in tooling costs. It is also a good idea to machine your first prototypes anyway. It is much less costly to get the bugs out of your design before you pay for tooling than after. The choice of process will also dictate some of the design features such as draft, fillet radii, and wall thicknesses.

I can make better recomendations after seeing some drawings. I could also do the machining or build tooling.

For the quantities you need, die casting aluminum is likely the best way to go. Investment casting is way too expensive unless there are under cuts in the shape. Sand casting is less expensive but requires more finish machining and does not look as good. Regardless of the process I recomend you have some prototypes machined including whatever draft and other features that will be required for the production process and try them. It will save you in the long run because it can cost nearly as much to rework a mold or tooling as it does to build it the first time.

There are also a number of reinforced plastics that might meet the physical requirements and could be molded for less than aluminum parts.