Ex.15 Read the text and answer the questions

Exercise 14. Read the text and answer the questions below (“Comparison of mechanical and tribotechnical properties of UHMWPE reinforced with basalt fibers and particles” by S.V.Panin, L.A. Kornienko, VO Alexenko, Huang Qitao1 and L.R. Ivanova).

Composites based on ultra-high molecular weight polyethylene (UHMWPE) are widely used in various industries. The application of composite materials with the UHMWPE matrix makes it possible to multiply increase the wear resistance of “metal-polymer” friction units. Recently, micro- and nanocomposites based on UHMWPE are actively developed.

At design of composite materials based on UHMWPE matrix their preferential operation conditions are to be taken into account: 1) abrasion wear (e.g. liners of transporters or carriages); 2) dry sliding friction (gear wheels or gear transmission); 3) friction under boundary lubrication (polymer сomponents of artificial joints).

During in-field exploitation the products made of UHMWPE matrix may experience all three abovementioned types of wear. In this concern it is reasonable to use the fillers that can provide improvement of wear resistance to various types of wear, as well as to provide higher strength, lower friction coefficient, etc. In doing so, various particulate and fibrous materials are used to fill the polymers.

Note that composites filled with the basalt fibers are actively developed. This is related to their high mechanical properties, low cost and ecological compatibility, since the basalt is a natural mineral, whose main chemical components are SiO2, Al2O3, CaO, MgO, Fe2O3. The melting temperature of the basalt makes 1500-1700 C.

Regardless the fact that results on studying UHMWPE composite materials filled with the basalt fibers are reported in the literature the topic on the influence of filler size and shape are of particular importance in the sense structure formation as well as mechanical and tribotechnical properties.

This paper deals with the comparative analysis of basalt fibers and particles reinforced UHMWPE composites. The issues of structure formation as well as mechanical and tribotechnical properties under dry sliding friction and abrasive wear are studied.

 

1.What is a piece of research the writer has conducted?

2. Did the writer give an answer to a question that he/she has been given or chosen?

3. Was it a subject of common interest?

4. Did he (writer) manage to synthesize research done by others on a topic?

5. What are the most common requirements to an academic text?