Properties and in-service performance of components reated with thermo reactive deposition/diffusion

Abstract

Properties and in-service performance of components reated with thermo reactive deposition/diffusionPropiedades y desempeño en servicio de componentes tratados con deposición/difusión termorreactiva ABSTRACT Machine components and tools subjected to aggressive environments and strong wear conditions need surfaces with good mechanical properties. The thermo-reactive deposition/diffusion (TRD) process is one of the methods used for improving the mechanical properties of these components and tools, mainly because of its low cost and good performance of the coatings deposited. Although the TRD process is widely used for coating dies, extrusion tools and punches among others, the in-service performance of cutting tools coated using the TRD process has not been extensively studied. In this study, niobium carbide coatings were deposited on cutting punches and screw taps using the TRD technique. Phase formation and micro-hardness of the coatings were studied using X-ray diffraction and Vickers measurements respectively, and the in-service performance of the coated and uncoated tools was studied through field tests conducted at different numbers of cuts. The results show that the coating significantly improves the wear resistance and the cutting performance of the tools, especially at higher numbers of cuts. RESUMENLos componentes de maquinaria y las herramientas sujetas a ambientes agresivos y fuertes condiciones de desgaste necesitan superficies con buenas propiedades mecánicas. El proceso de deposición/difusión termorreactiva (TRD) es uno de los métodos usados para mejorar las propiedades mecánicas de estos componentes y herramientas, principalmente por su bajo costo y buen desempeño de los recubrimientos depositados. Aunque el proceso TRD es ampliamente usado para recubrir moldes, herramientas de extrusión y punzones entre otros, el desempeño en servicio de herramientas de corte recubiertas usando el proceso TRD no ha sido estudiado extensamente. En este estudio se depositaron recubrimientos de carburo de niobio sobre punzones de corte y machos de roscado usando la técnica TRD. La formación de fases y la microdureza de los recubrimientos se estudió usando difracción de rayos X y dureza Vickers

An Overview on the Corrosion Behavior of Steels Processed by Severe Plastic Deformation

“…In many applications, tool steels are coated with transition metal carbides to improve corrosion resistance. Some authors report the improvement in the corrosion resistance of AISI D2 (111,112,113,114,115,116,117) and AISI H13 115) tool steel with the production of a layer of chromium niobium carbide on the steel surface, and other works have reported that for tool steels the corrosion behavior could be more influenced by its phase composition that the nanocrystalline structure (118) .…”