Determination of wear resistance and wear mechanisms of HVAF coat-ings based on Ni-Al composition depending on the technological modes of their deposition

A Dovhal,L Pryimak,I Trofimov

doi:10.31891/2079-1372-2020-95-1-26-33

Abstract

Presented studies are related to the spheres of aviation and machine-building. World aviation technology experience has accumulated a huge amount of statistical material on the failure airborne systems and ground equipment due to the increased level of parts wear. That is why the issue of research and improvement of anti-wear properties aeronautical parts is one the components when considering the priority directions of ensuring the reliability of operation motor vehicles and friction units. The Ni3Al coating has been deposited on the medium carbon steel using high velocity air fuel deposition. It has been established that it is very sensible for modes of coating deposition and different chemical phenomenon have been detected. The structure of the obtained coating has been thoroughly researched on the electronic microscope. The obtained coating has been tested on the friction bench modeling the fretting process that is taking place in the couple of locking devices of self-propelled passengers stairs. The coating has also corrosion protection. The friction surfaces have been investigated on the electronic microscope and the wear mechanisms have been established. The optimal modes of the HVAF coting deposition from the viewpoint of wear resistance have been detected

Highlights

One of the important problems of modern technological processes at airports is the technological, safe and efficient operation of aviation ground equipment used for ground handling of aircrafts
This is determined by the strength and resource of ground support equipment, the resource and safety of which are generally determined by the efficiency of triboelements, which can be substantially improved by technological measures of surface hardening, in particular the application of protective coatings
The technology of high-speed air-fuel spraying (HVAF) wear-resistant coatings is widely used in various industries for powder compositions

Summary

Introduction

One of the important problems of modern technological processes at airports is the technological, safe and efficient operation of aviation ground equipment used for ground handling of aircrafts. The process of friction in the couple of teeth of the locking latches and hooks of the sliding section corresponds to the fretting wear with the elements of the corrosion process if the paint coatings are being destroyed. The frequencies are of two types: low frequencies, which have no regular frequency and are extremely rare, and the fundamental oscillation frequency of the friction pair is the forced frequency from the rotation of the engine of the special machine at the rated mode of operation, which is 1600 - 1800 rpm, and corresponds to the oscillation frequency in 30 Hz. The loaded area of the contact tooth can be protected by a coating of a composition based on nickelaluminum intermetallide, which is well established as a protective composition

Review of the latest research

Factors that significantly affect the structure of the coating

Findings

Conclusions