Porosity and Water Absorbability of Tool Composite Materials as Factors of Improving Wear Resistance of Superabrasive Grinding Wheels. Part 2. Water Freezing in Porous Space of Superabrasive Composites

A series of substituted polybenzoxazines was synthesized and studied as binders in non-asbestos friction composite materials. The structures of the polybenzoxazines were varied in a systemic fashion by increasing the number and position of pendant alkyl (methyl) groups and was accomplished using the respective aromatic amines during the polymer synthesis step. By investigating the key thermomechanical and tribological characteristics displayed by the composite materials, the underlying structure-properties relationships were deconvoluted. Composite friction materials with higher thermomechanical and wear resistance properties were obtained from polybenzoxazines with relatively high crosslink densities. In contrast, polybenzoxazines with relatively low crosslink densities afforded composite friction materials with an improved coefficient of friction values and specific wear rates.

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A DEVICE AND TOOL FOR MAKING SAMPLE FROM POLYMER COMPOSITE MATERIALS ON A CNC MACHINE (review)

Proceedings of VIAM ◽

10.18577/2307-6046-2021-0-4-100-109 ◽

2021 ◽

pp. 100-109

Author(s):

M.I. Minibaev ◽

◽

M.N. Usacheva ◽

V.S. Dyshenko ◽

V.A. Goncharov ◽

...

Keyword(s):

Wear Resistance ◽

Composite Materials ◽

Carbon Fiber ◽

Sheet Metal ◽

Polymer Composite ◽

Carbon Fiber Reinforced Plastic ◽

Cnc Machine ◽

Fiber Reinforced Plastic ◽

Advantages And Disadvantages ◽

Reinforced Plastic

The article discusses devices for fixing sheet metal blanks from PCM: a perforated vacuum table, its design features, advantages and disadvantages. Based on these data, the upper part of the vacuum table was made for cutting samples for Iosipescu tests and dielectric tests. The article describes various types of tools for PCM processing and an experiment on the wear resistance of a diamond-like coated rasp cutter when milling carbon fiber reinforced plastic, carried out by foreign researchers.

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THE INFLUENCE OF THE COMPOSITION AND SIZE OF THE FRACTIONS OF THE COMPOSITE GRAVEL FILLER WITH AN EPOXY MATRIX ON ITS WEAR

Tekhnicheskiy servis mashin ◽

10.22314/2618-8287-2021-59-3-100-107 ◽

2021 ◽

Vol 3 (144) ◽

pp. 100-107

Author(s):

Aleksandr M. Mikhal’chenkov ◽

◽

Anna A. Tyureva ◽

Ivan A. Borshchevskiy ◽

Larisa S. Kiseleva

Keyword(s):

Wear Resistance ◽

Composite Materials ◽

Epoxy Matrix ◽

Protective Coatings ◽

Research Purpose ◽

Effective Diameter ◽

Wear Process ◽

The Matrix ◽

Sand And Gravel ◽

Over Time

The widespread use of polymer-based composite materials made it possible to replace expensive metal alloys, increase the strength indicators of structures and improve tribotechnical properties. Their use as protective coatings for structural elements operating in an abrasive environment has yielded good results in increasing wear resistance, which is especially important for parts of tillage tools. (Research purpose) The research purpose is in studying the influence of the composition and size of the fractions of the composite gravel filler with an epoxy matrix on its wear. (Materials and мethods) The article considers five composite materials with different compositions. The prototypes were hollow cylinders with dimensions that provide the contact area necessary for the passage of all processes of abrasive wear. The abrasive composition consisted of a mixture of sand and gravel with a fraction size of about 30-40 millimeters. (Results and discussion) The changes in the wear over time are directly proportional and this confirms the classical views on the wear process. The experiments was conducted on the installation of authors’ design. (Conclusions) The wear over time for experimental composites is the same and is expressed in a straight- line relationship; the maximum wear resistance is a composite in which gravel particles have a size of 2.25 millimeters with its content in the matrix of about 60 mass parts. At the same time, gravel with an effective diameter of 2.25 millimeters creates optimal conditions for self-organization of the wear process and provides a relatively low value of the friction coefficient.

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