I need to know what grade steel the housings are made from to get them nitrided. Any info will help

 

they arent made of steel they are made of aluminum.

 

There are 2 rotor housings and they are made of aluminum and a front, intermediate, and rear side housings that are made of steel.

Obviously, I am talking about the steel housings... Especially, since you dont nitride the aluminum rotor housings.

 

What your talking about are the Side housings 3 in total and they are just made of cast iron like an old v8 big blok just plain cast iron not steel.

 

What level of carbon is present? wouldnt it be considered steel if low amounts of carbon?

 

umm, the rotor housings have a steel insert that the apex seals ride on........

 

"Insert" is a wrong word there. It's more like a chromium plating on I believe Nickel. Insert would be more like a steel/chromium insert used for cylinders in a piston engine block.

Oh, and regarding the "iron" cast housings, I'm pretty sure they're steel (enough carbon content there). Someone call an engineer...

 

Iron has carbon in it, it depends on the amount whether it's called steel or iron.

 

The housing is made of aluminum... I asked about the steel housing, not the steel insert on the aluminum housing....

 

I thought it was over 5% carbon or something then it is considered Iron and less than that it is steel. The more carbon with the iron the more brittle it is.

 

the housings are more like a sleeve then chrome plating go to Mazdatrix.com and click the cool things link there is a link there to see how rotaries are built they use a sheet metal sleeve and cast the aluminum around it... now for the sides they are cast iron

http://en.wikipedia.org/wiki/Cast_iron

the second paragraph says that the carbon content of cast iron is 2.1 or 4% while ferrous alloys with less carbon content are considered carbon steel...
if your getting them re-nitrided there are some shops that do specific nitriding for rotaries but if you tell them its cast iron they will know whats going on because cast iron is cast iron...

 

Ok, Ill clarify so there is no more discussion about the aluminum rotor housings. I want to know the grade of steel for the rear, intermediate and front side housings.

Here is a picture so there is abosolutely no more confusion.

 

They are cast iron. Just like an iron piston engine block. They will break but not bend. They are also nitrided on the wear surface. Cast iron. That is what they are made of.

 

FWIW, Mazdatrix makes the "irons" out of aluminum (they make new blanks with no ports) and the new 16X rotary engine will also utilize aluminum "irons".

I think that gives an indication of the versaility of the material used for the plates. I however can't comment on the composition of the OEM plates since I don't know.

 

Ok, so they have a carbon content of over 5%, do you know what the number is?

 

click my wikipedia link it tells you the technical specs on cast iron you cant get the % number exactly because every time the metal us smelted the % is a little different!! why do you need to know the % so bad?

 

Mazdatrix re-sells the aluminum "irons" that Racing Beat makes.

 

The company I am talking to about nitriding the housing wants to know the exact composition of the iron/steel to be able to do the best job is what they told me. They said if the housings are high carbon content iron they think Ferritic Nitrocarburizing (FNC) would be a better option.

 

well they are high carbon iron what I would do is give mazdatrix a call and see what there professional opinion is, they might know the exact composition, but cast iron is high carbon by nature 4% of carbon is like turning steel into glass good high carbon steel has a carbon content of around 2.0% it takes 1.8% of carbon to turn iron into steel ad another .65% and it will turn it into high carbon steel, so what does this guy consider high carbon because the sides being made of cast iron denotes they are high carbon.

I hope this clarifies things, like I said earlier though I would look into talking to one of the major rotary rebuild shops like mazdatrix.com pineappleracing.net (pineappleracing.com is not up) or atkinsrotary.com see what they think where they might suggest to go and what they have had success with.

 

you do realize those things cost like 3X the cost of oem ones and if he is having his re-nitrided then he is looking to save some money no?

 

Most people wouldn't care the classification of cast iron / steel.
Only the engineers and geeks would care about that kinda stuff.
I don't think I've even seen a spec given out by Mazda.

Nitriding or "gas nitriding" can be done to almost any surface...including aluminum.
I believe the Racing Beat aluminum side "irons" are nitrided also?

Actually, that stainless steel liner is considered an "insert".
It's not a plating.
The chrome over the stainless steel liner is considered "plating".
Technical specs on this can be read in SAE papers and also in the Jack Yamaguchi RX-7 book.

If you really insist on getting the exact composition of the cast iron why not send it out for material analysis?
I doubt you'd get a solid answer from asking us...


-Ted

 

The reason I asked here first was to save myself that step of sending it out, especially if someone else has already done that.

The guy wanted to know close to the composition because he wanted to try that FNC process on the housing instead of nitriding. Apparently, it is better for sliding friction than nitriding and will warp the housing less.

 

What part of that didn't you understand?


-Ted

 

what part of this didnt you understand? i doubt that everyone on the forum has seen this thread, so there may be someone here that knows the answer. also, i guess according to you there are no geeks or engineers on this forum, that might know the answer?

 

Lets not fight. I seriously doubt anyone's done that, as even the high end shops don't seem to be re-nitriding ground or lapped irons.