Material Technology in Manual Transmissions

[MolaKule]

Except for Class 8 HD truck transmissions which consist mainly of steel components and use a 50 grade transmission lubricant, many automotive and light truck transmissions still use brass synchronizers and a lower viscosity dedicated MTF.

The alloys in the brass synchronizers consist of the following metals in these approximate ratios:

Copper - 60%
Zinc - 27%
Aluminum - 1.7%
Manganese - 2.5%
Lead - 0.3%
Silicon - 0.9%

The inclusion of manganese, aluminum, and silicon increases the hardness and strength of the brass alloy.

What would be another reason for aluminum to be included in this alloy?




Guidelines for the Question of the Day:

1. No Piston Cup Lapel Pin will be awarded to the same person within 14 days of a previous award.

2. Please respond with a complete sentence or explanation.

3. Please do not post links. If a question arises as to the need for clarification, then sources and links may be requested.

4. Please, no off topic posts.


Reference:
http://www.bobistheoilguy.com/forums/ubb...sio#Post1231182

See post #2813713

 

[Shannow]

Corrosion Resistance

(have changed out hundreds of tonnes of Al Brass)

 

[Rolla07]

The addition of Aluminum increases its resistance to corrosion (as Shannow said), and high impact load since brass is stronger with it, and less likely to corrode without it.

 

[mjoekingz28]

Increase malleable
Decrease ductile
.????????

 

[MolaKule]

Thanks to all who answered.

The additional affect of having aluminum content as part of the alloy is that the adhesive layers of aluminum oxide are formed that lead to greater corrosion resistance against any additive break-down product(s).

So Brass Synchronizer components are MORE likely to corrode without the inclusion of aluminum.

So Shannow get the Piston Cup Lapel Pin.

 

[Shannow]

Thanks MolaKule, can I have it in 90:10 cupronickel ?

Al Brass has caused me too much heartache over the years (like how to remove 160 miles of tube, and replace it with new in 9 weeks)

 

[MolaKule]

Originally Posted By: Shannow
Thanks MolaKule, can I have it in 90:10 cupronickel ?

Al Brass has caused me too much heartache over the years (like how to remove 160 miles of tube, and replace it with new in 9 weeks)


CUpronickel it is.