Desenvolvimento de dispositivo e estudo do comportamento ao microdesgaste abrasivo do aço AISI 420 temperado e revenido

Abstract

O objetivo deste trabalho é a construção de um dispositivo para a realização de ensaios de micro desgaste abrasivo por esfera fixa. O contato abrasivo é realizado por uma esfera de aço AISI 52100, a qual é presa num eixo que gira com grande precisão, com ajuda de um motor, em relação a uma amostra plana que se manterá estacionária. A carga normal de ensaio é aplicada através de ajustes de peso no suporte pivotado do corpo de prova, a qual pode ser variada a cada ensaio realizado. Este dispositivo foi utilizado para a determinação da resistência ao desgaste abrasivo e da eficácia de tratamentos de superfície utilizados em peças que sofrem este tipo de solicitação em serviço, além de utilizá-lo para estudar novos produtos desenvolvidos para o aumento de resistência ao desgaste de superfícies. Foi avaliada a resistência ao microdesgaste abrasivo de aço AISI 420 temperado e revenido. Observou-se que o aumento da dureza do material tratado aumentou a resistência ao desgaste abrasivo quando comparado com o material sem tratamento térmico.Palavras-chave: desgaste microabrasivo, esfera fixa, aço AISI 420, configuração experimental. ABSTRACTThe abrasive microwear testing has been the subject of a significant amount of research in recent years, when its potential to evaluate the behaviour of thin coating became relevant. The aim of this work is to build a apparatus for abrasive microwear testing by rotating sphere. The abrasive contact is performed by a AISI 52100 steel ball which rotates, with great accuracy with the help of an electric motor, in relation to a flat sample that will remain stationary. The normal load is applied by weight adjustments in the support of the test specimen, which can be varied for each performed test. This device was used to determine the abrasive wear resistance and effectiveness of surface treatments used in parts that undergo this kind of requirement in service, and also for studying new products developed for increasing the wear resistance of surfaces. The microwear resistance of the quenched and tempered AISI 420 steel was evaluated. It was observed that increasing the hardness of the treated material produced an increased wear resistance when compared with untreated material Keywords: microabrasive wear, rotating sphere, stainless steel AISI 420, experimental setup. INTRODUÇÃOA palavra tribologia, derivada do grego, significa estudo do atrito, sendo a ciência e tecnologia que estuda a Matéria, v.20, n.2, pp. 304 -315, 2015.

Abrasive effects of sediments on impellers of pumps used for catching raw water

“…Wear coefficient is calculated based on the volume of material removed during the test, using Eq. 5 (Rutherford & Hutchings 1997;Allsopp & Hutchings, 2001;Santos et al, 2015;Krelling et al, 2017). Figure 2.…”

Methodology for Abrasive Wear Evaluation in Elevator Stage Centrifugal Pump Impellers

“…The abrasive slurry was dripped onto the wear interface. After the sphere travels through a previously established distance, called a running distance, a circular depression or crater of wear occurs on the surface of the sample [9,10,[17][18][19][20][21]. Figure 4 shows a schematic diagram of the microabrasion test device.…”

“…After the wear tests, the simplest technique for the calculation of the wear coefficient is based on the reading of the average diameter of the crater formed by the wear followed by the application of Eqs. (35)-(37) presented below [9,10,17,18,20,21]. The diameter measurement should be performed by scanning electron microscope (SEM).…”

“…The estimated wear of the impeller blades was predicted based on the modified Archard equation [20], where the coefficient of wear (k) presented in Eq. (1) is a dimensionless constant that is divided by the hardness of the worn material (H) and that the K displayed in Eq.…”

Micro Abrasive Wear Behaviour Study of Carburization and Ion Plasma Nitriding of P20 Steel

“…The fixed ball test system is broadly used to study the microwear in a variety of materials. The micro abrasive wear tests were carried out using a fixed ball microwear device, as can be seen in Figure 1 10 . In this technique, a ball often of bearing steel, is pressed against the test sample in the presence or absence of abrasive slurry.…”