aluminium coating

[123raoel]

My name is Roel and I'm a Belgium student working on a project for an English company during my 5 months placement.

Till now I had never worked with coating and so I have no ideas what is possible and what's not.

I would like to do some tuning in a gas turbine with an aluminium coating or an alloy.

I need a material that is elastic enough and expand with the temperature to work as a sealing, there for I thought on aluminium.

The temperature in that part of the turbine is max. 200 C.

The coating should be 0.4mm or even more?

I have tables and info about aluminium but have no ideas at the moment with what material the coating happens itself

Does what I write make and sense and is this possible?

Are there info sites where I can do research in tables?

Many thanks and hopeful one of you can help me

Roel

[Gordon]

Hi Roel

to the Surface Engineering Forum.

Aluminium based coatings are commonly used as abradable or clearance contol coatings in gas turbine engines.

I think you should start by searching terms like "abradable coating" and "clearance control coatings" on this site and in the likes of Google and see if that helps.

[123raoel]

dear

thank you already for the anwser.

What do you think of following calculation of Expansionby heat:

Temperature difference: 190 C
Linear expansion coefficient of alu: 0.0000239mm per C
Start thinness of the coating 0.5mm

0.5*0.0000239*190=0.0022705mm

thikness after heating: 0.5022705mm

Roel

[Gordon]

Hi Roel

Your calculation looks ok. But this will be not be very significant and only a small part when considering effect of thermal movement on the whole working assembly. Linear expansion coefficient should also be considered in 3 dimensions. Expansion circumferentially will be more significant. Properties of substrate and counter parts are probably going to be far more important considerations.