Development of metal composite materials with macroheterogeneous structure (MCMMS) for the application in friction pairs working in heavy conditions

Nezavisimosti ave, 65, Minsk, Belarus, 220013

Ph/fax: +375 (17) 292 85 05

E-mail: kvlad@bntu.edu.by 

Uladzislau Kalinichenko

 

We created new compositions of MCMMS based on the metallic matrix reinforced with rapidly solidified iron base granules or hard alloy particles. MCMMS are able to work under the high specific load matched with low sliding velocities and the elevated temperature when most tribological materials are unable to perform.

The production of MCCM parts is based on the casting technology. As a result the cost of these composite materials are lower compared to ones manufactured via a powder metallurgy route but with better performance. The additional advantage is that the secondary nonferrous alloys and scrap can be used to cast composite parts. The casting technology is characterized with good flexibility resulting in the production of the complex shape parts without any limitations in parts’ sizes.

Casted composite materials were successfully applied to produce parts for the installation under the frame of the turbine’s bearings support aiming the normalization of the turbine’s thermal expansion.

Moreover some roller bearings can be replaced in friction units with plain bearings made of MCMMS. It is especially useful when the friction pair is working under the elevated temperature as the composite materials developed keep their ability to perform at the temperature up to 500 oC.

Another attractive feature of the MCMMS is the ability to form the friction film resulting in the considerable reduction of wear and the increase of the service life.

The additional increase in the reliability of friction parts and the service life can be achieved with the application of solid lubricative coatings, which are modified with special additions.

These materials can be used for the production of such friction pairs as driving screw-bush, oil mining equipment, transport, machines for road construction etc.

We are ready to collaborate on the different base including the joint research, production of experimental sets of composite bearings for different application or within the commercial projects.

Some data for composites made of bronze matrix and reinforced with iron based granules:

- Compression strength up to 1700 MPa

- Yield strength up to 350 MPa

- Friction coefficient (dry friction) 0,08-0,1

- Friction coefficient with solid lubricative coatings modified with special additions 0,006-0,05

MCMMS plain bearings for the application in the system of the steam distribution