Can automotive part casted with pure zinc?? 1

[Metallic007]

Can anyone please advise whether an automotive part can be casted with PURE zinc (~99.3%)?

From what I know, the typical zinc alloy for casting is ZA alloys and ZAMAK alloys, which contain appreciable amount of aluminium.

Thanks.

 

[3DDave]

Given the lack of information on the Internet about casting pure Zinc I would say that while it seems possible, it also seems that there are significant problems doing so. If there weren't casting houses would list it. Aluminum seems to be added to increase the strength and other minor alloying metals are there to lower the surface tension so the mold fills more easily.

Since it seems specialized, I suggest that you contact potential casting houses and ask them what affect this pure metal might have on their ability to cast and therefore the design to use it.

 

[SnTMan]

Suspensions arms or radio knobs?

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[Metallic007]

Thank you for your information 3DDave.

Mike (SnTMan), the casted part is air connector for break system of a truck.

 

[arunmrao]

Are you not able to source Zamak alloy in small quantities, that you want to use pure Zinc metal . You can try using some of the old and broken toys as raw material.
Are you going to use rubber mold to cast the parts.

"Even,if you are a minority of one, truth is the truth."

Mahatma Gandhi.

 

[Metallic007]

Dear Gandhi

I am not going to cast the part. I have this new set of air connector and chemical analysis revealed that it contains 99.7% zinc. I just wonder why would someone cast this part with pure zinc and not the typical zinc alloy.

 

[arunmrao]

Who is Gandhi here,I don't know.

You are now coming with more information regarding the part. At least I understood that there was a need to cast a part in Zinc.

"Even,if you are a minority of one, truth is the truth."

Mahatma Gandhi.

 

OK, I am now officially confused.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[metengr]

I have this new set of air connector and chemical analysis revealed that it contains 99.7% zinc.

Was this an actual chemical analysis (OES or other) or PMI? The zinc could be from galvanizing on the surface.

 

[Metallic007]

Metengr.

Thank you for your information. I have now went further by cutting a cross section of it and tested it with a XRF analyser. The test result still show the same with 99.7 % of zinc with traces amount of Cu.

Is it possible that the fabricator was trying to save cost and cast the part with only pure zinc?

Thanks.

 

[ornerynorsk]

First of all it would be worthwhile to calibrate any instruments you are using for analysis. In my mind, there would be no advantage to use pure zinc for anything except plating anodes. The alloys all have superior properties, as others have stated. Any reason to do so would have likely been economic.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[racookpe1978]

You may have a bad part. A fake duplicate that is not properly spec'ed out, purchased, nor analyzed.

Could be a deliberate error (fraud, since zinc casting would be cheaper to make); could be an error that happened at the manufacturer or the supplier of the product. Cast zinc is brittle, looks pretty, and has no strength. There is no reason for it to be used ANYWHERE near a pressurized brake system, nor anything more important than a children's toy safely placed on a shelf well above the child's hands. (Choking hazard from the broken pieces accepted.)

 

[mrfailure]

I hope that truck is not the vehicle behind me!

Even though you have portable XRF results, I still would suggest that you send it to a lab that can do a quantitative chemical analysis and have them identify the alloy.

 

[SwinnyGG]

I would bet that you're still getting the plating in your analysis. Sectioning a thin part, like a fitting, and then trying to get a chemical analysis of the thin layer of base metal between the two plated surfaces is a task that requires a very high level of skill in preparing samples.

 

[mrfailure]

A lab analysis will eliminate the plating results jgKRI mentioned by stripping it off before testing.

 

[Metallic007]

Dear All

Thank you for the comments. I have done a metallographic examination of the cross section and no plating or coating is revealed from the microstructure. This would indicate that the XRF result is accurate.