Jose L. Mier

University of A Coruña | UDC · Department of Industrial Engineering

This work proposes a green material for artificial reefs to be placed in Galicia (northwest Spain) taking into account the principles of circular economy and sustainability of the ecosystem. New concrete formulations for marine applications, based on cement and/or sand replacement by mussel shells, are analyzed in terms of resistance to abrasion. T...

This work studies the influence of the saline atmospheric corrosion on the fatigue strength of 6061-T6 aluminum alloy. For this purpose, this alloy was subjected to tests in a salt spray corrosion chamber at different exposure times (1, 2, and 3 months) according to ASTM B117 standard. The morphological study of the pits was carried out by confocal...

This paper studies the microstructural and tribological differences of layers formed during the ferritic nitrocarburizing of AISI 4340 alloy steel and AISI 347 stabilized stainless steel. The samples were exposed to different times of immersion in a nitrocarburizing bath (60, 75, 90, 105 and 120 min) at 580 °C. Subsequently, they were subjected to...

This study shows the effects of wear on welded joints of ASTM A355 Gr. P11 “Seamless Ferritic Alloy-Steel Pipe for High Temperature Service” steels subjected to the welding procedures established by codes B31.1 and ASME III. The standard welding procedure establishes the following steps: a preheating process, welding and post-weld heat treatment. T...

Este trabajo estudia las diferencias microestructurales y tribológicas de las capas formadas durante la nitrocarburación ferrítica del acero aleado AISI 4340 y la nitrocarburación austenítica del acero inoxidable estabilizado AISI 347. Las muestras se sometieron a distintos tiempos de inmersión en un baño de nitrocarburación (60, 75, 90, 105 y 120...

This paper presents an alternative to the materials traditionally used in the manufacture of coal mills for coating wedges. For this purpose, we designed and tested ten new austenitic steels with medium manganese content. The thermal structural stability and hardness were evaluated after different heat treatments. The steels were subjected to hyper...

This work studies plastic behaviour and its influence on the abrasive wear resistance of a group of high chromium white cast irons. The irons were poured in metallic moulds and heat treated. The studied alloys have 3% C, 12% Cr, as well as 0.6% and 2.4% Si. The plastic characteristics are evaluated through the parameters obtained from Meyer's test:...

Wear resistance, corrosion properties and structure of reinforced layers deposited on steel AISI 321 with carbonitriding by the quench-polish-quench (QPQ) Tennifer® process with subsequent oxidation are studied. The structure of the layers is investigated by scanning electron microscopy with energy dispersive local analysis and x-ray diffractometry...

The tribological and mechanical properties of various cast irons with different contents of carbon and silicon are studied. The Brinell hardness or every cast iron was measured and their wear resistance was calculated according to ASTM G99 standard, "Standard Test Method for Wear Testing with a Pin-on-Disk Apparatus. These results were related to m...

Wear is one of the most worrying problems in industry; it affects many production sectors. Therefore, the wear resistance of materials must be assessed in order to predict their response and anticipate possible failures. Maintenance could then be scheduled accordingly. Due to the large number of situations where wear is important, one of the main c...

The influence of silicon content and heat treatment on microstructure, abrasive and dry friction wear resistance of a 3 % C, 12 % Cr cast iron, under fast solidification conditions is studied. The fast solidification condition diminishes the carbide volume and the silicon content increases their dispersion and finesses. All matrixes obtained were p...

The tribological and mechanical properties of five cast-iron with different contents of carbon and silicon have been studied.Wear tests according ASTMG99 “Standard test method for wear testing with a pin-on-disk apparatus” and Brinell hardness measurements were carried out in every alloy. These results were related to microstructure, composition an...

This study analyzes the wear behavior of austenitic Hadfield steels with different manganese contents (4 to 6% of manganese). The tribological analysis has been carried out by pin on disk tests according to ASTMG99-05 standard. The results have been related to the hardness and to the microstructure of every sample. The wear resistance of these stee...

A mathematical model for the total heat flow obtained in differential scanning calorimetry (DSC) experiments from polymers with enthalpic relaxation is proposed. It is limited to the glass transition and enthalpic relaxation range of temperature and to the cases where the enthalpic relaxation is the only non‐reversing process taking place. The mode...

Vegetable oils of different types and qualities are widely used in homemade cooking and food industry. Most of the safety concerns were related to possible oxidation processes produced at the relatively high temperatures used when frying. Thus, the thermal stability to oxidation is an important parameter for edible oils. Oils from the Arbequina, Pi...

The oxidation stabilizing effect of a substituted phenol on soy and palm based biodiesels was investigated according to the ASTM E2009 standard. Pressure differential scanning calorimetry (PDSC) measurements were used to evaluate the influence of oxygen pressure. A relationship was derived to describe the correlation between oxidation onset tempera...

This paper compares the abrasive wear behaviour of two nickel alloys (Hastelloy and Refractalloy). Wear was calculated by weight loss using pin-on-disk tests that were carried out at certain values of load, speed, and temperature range. The study is completed with metallographic observations at different temperatures of the wear tracks before and a...

In this study the effect of the level of oxygen pressure, the concentration of antioxidant and the type of biodiesel on the oxidative stability of the material have been measured. An experimental design was performed considering two types of biodiesel, various pressures of oxygen and additions of a commercial antioxidant. As a response variable was...

This study deals with the wear experienced in welded joins for pipelines. Its aim is to minimize the problems caused by this wear. An analysis is carried out on the tribological behaviour of three crucial areas within the welding: the base metal, the heat affected zone and the weld bead zone itself. The differences in mechanical properties between...

The oxidation stabilizing effect of a substituted phenol on soy and palm based biodiesels was investigated according to the ASTM E2009 standard. Pressure differential scanning calorimetry (PDSC) measurements were used to evaluate the influence of oxygen pressure. A relationship was derived to describe the correlation between oxidation onset tempera...

In this study the effect of the level of oxygen pressure, the concentration of antioxidant and the type of biodiesel on the oxidative stability of the material have been measured. An experimental design was performed considering two types of biodiesel, various pressures of oxygen and additions of a commercial antioxidant. As a response variable was...

En este trabajo se ha cuantificado la influencia que tiene la clase de biodiesel, la presión de oxígeno y la concentración de un antioxidante sobre la estabilidad a la oxidación del biodiesel. Para ello se realizó un diseño experimental considerando dos tipos de biodiesel, distintas presiones de oxígeno y adiciones de un antioxidante comercial. Com...

This work studies the abrasion wear behavior of four cast irons: white iron, ferritic ductile iron, ductile iron with boron and Ni- hard. Chemical composition and metallographic structure were determined in all of them. The abrasion wear behavior study was carried out by pin on disk test setting load, speed and pìn material and calculating the weig...

By adding boron to the liquid metal, it is possible to obtain spheroidal graphite cast iron without any need for special inoculants. The boron may be in metallic form; alternatively, borax, ferroboron, boron carbonate or borocalcium can be used. These alloys as cast present a pearlite matrix with more or less spheroidal graphite, which is usually e...

By adding boron to the liquid metal, it is possible to obtain spheroidal graphite cast iron without any need for special inoculants. The boron may be in metallic form; alternatively, borax, ferroboron, boron carbonate or borocalcium can be used. These alloys as cast present a pearlite matrix with more or less spheroidal graphite, which is usually e...

Abstracú. This work studies the behaüour of welding joints under abrasive wear in A355 Gr. Pl I steel pipes carrying liquids at high temperatures. Various welding processes were tested on different joints in an effort to choose the one that gave the best wei¡r response. Forthis purpose, apin-ondisk fribometer was used úz0ff.C to simulate the servic...

The logistic mixture model was successfully studied previously in the separation of overlapping steps in some polymeric systems by the authors. In the present work, this method is applied to a polyesther-polyurethane degradation under air and inert atmospheres at several heat rates (5, 10, 15, 20 and 25 °C/min) in dynamic TGA. Every logistic compon...

This work studies the behaviour of welding joints under abrasive wear in A355 Gr. P11 steel pipes carrying liquids at high temperatures. Various welding processes were tested on different joints in an effort to choose the one that gave the best wear response. For this purpose, a pin-on-disk tribometer was used at 200°C to simulate the service condi...

This study deals with the wear experienced in the welded joins for pipelines. Its aim is to minimise the problems caused by this wear. An analysis is carried out on the tribological behaviour of three crucial areas within the welding: the basic metal, the heat-affected zone and the weld bead zone itself. The differences in mechanical properties bet...

This study deals with the wear experienced in the welded joins for pipelines. Its aim is to minimise the problems caused by this wear. An analysis is carried out on the tribological behaviour of three crucial areas within the welding: the basic metal, the heat-affected zone and the weld bead zone itself. The differences in mechanical properties bet...

This study deals with the wear experienced in the welded joins for pipelines. Its aim is to minimise the problems caused by this wear. An analysis is carried out on the tribological behaviour of three crucial areas within the welding: the basic metal, the heat-affected zone and the weld bead zone itself. The differences in mechanical properties bet...

Cited By (since 1996): 1, Export Date: 6 August 2012, Source: Scopus

The aim of this paper is to evaluate and explain the fitting of dynamic TG curves by a mixture of logistic functions. This model assumes that more than one physical process may be involved in each mass loss step and that each physical process may extend along all the experiment. One of the main sources of difficulties in TG is that, very often, dif...

A diglycidyl-ether of bisphenol-A (DGEBA)/Triethylenetetramine (TETA) system was studied by non-isothermal differential scanning calorimetry (DSC) to establish its kinetics of cure The DGEBA resin was Araldite GZ 601 X75 used in the marine coatings formulations. Previously, the optimum resin/hardener ratio was determined by the reaction heat measur...

Cited By (since 1996): 1, Export Date: 6 August 2012, Source: Scopus

This study examines how thermal treatment influences behaviour in the case of abrasion wear. The material's behaviour under abrasion wear was studied using the "Standard Test Method for Conducting Wet Sand / Rubber Wheel Abrasion Test" and the guidelines of the ASTM G105 regulation were followed. Also studied was the relationship between the micros...

It has been reported good mechanical performance, corrosion and oxidation resistance at high temperatures for many Ni-based super-alloys. They are used in the industrial applications where this excellent behavior at high temperatures is needed. The samples for this study were extracted from a used gas turbine rotor blade. Optical microscopy and SEM...

Knowledge of thermal behavior is needed when structural applications are concerned, and quick method of identifying species of wood is desirable in order to track the materials in industrial processes and in the life service Samples of wood from four different species of trees (Castanea sativa, Quercus robur, Eucalyptus globulus, and Pinus sylvestr...

Ni-based superalloys are usually employed in industrial applications where good mechanical performance, corrosion and oxidation resistance at high temperatures is required. Samples collected from a gas turbine rotor blade were used in the present study. The X-ray photoelectron spectroscopy (XPS) and inductive coupled plasma (ICP) techniques were us...

The nickel-titanium alloys are usually known as Shape Memory alloys because of their ability to return to some previously defined shape or size when subjected to the appropriate thermal procedure. Mechanical properties of a nickel titanium wire were investigated by DMTA using cylindrical tension mode. The Young"s modulus, the maximum strain and res...

RESUMEN En este trabajo se estudia el desgaste por abrasión de un acero al manganeso (5 % Mn) obtenido por moldeo utilizando el ensayo de "rueda de caucho y arena húmeda", según norma ASTM G105. Se estudia también la influencia de diferentes tratamientos térmicos en el desgaste de este acero, tratando de correlacionar microestructura y dureza con l...