Heat Treaters Research Articles

SAE 1025, CEN C25, ISO C25

Abstract 1025, C25, C25E, and C25R are wrought low-carbon (carbon = 0.22–0.29%) non-alloy steels that are used in the normalized, cold worked, or quenched and tempered condition. 1025, C25E, and C25R may also be nitrided or nitrocarburized. These steels are widely used for small, moderately stressed parts that require higher strength levels than can be achieved by the lower carbon grades, and also for applications that require a combination of moderate strength, high toughness, and good fabrication characteristics. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on forming and heat treating. Filing Code: CS-252. Producer or source: Heat Treater's Guide.

SAE 1030, CEN C30, ISO C30

Abstract 1030, C30, C30E, and C30R are wrought medium-carbon (carbon = 0.27–0.34%) non-alloy steels that are used in the normalized, cold worked, or quenched and tempered condition. 1030, C30E, and C30R may also be flame or induction hardened, nitrided, or nitrocarburized. These steels are widely used for small, moderately stressed parts that require higher strength levels than can be achieved by the lower carbon grades, They are also used for applications where a combination of moderate strength and good toughness is required. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on forming and heat treating. Filing Code: CS-249. Producer or source: Heat Treater's Guide.

SAE 1038, SAE 1038H

Abstract 1038 and 1038H are wrought medium-carbon (carbon = 0.34–0.43%) non-alloy steels that are used in the normalized, cold worked, or quenched and tempered condition. 1038 and 1038H may also be flame or induction hardened, nitrided, or nitrocarburized. These steels are widely used for moderately and highly stressed parts that require higher strength levels than can be achieved by the lower carbon grades, and where the expense of an alloy steel is not justified. Owing to their low hardenability, their use in the quench and tempered condition is not recommended for large sizes, as the improvement in mechanical properties over the normalized condition is insufficient to justify the additional cost of heat treatment. 1038 and 1038H are among the most widely used steels for threaded fasteners. Their popularity stems from their excellent cold-heading properties, low cost, and wide availability. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on forming and heat treating. Filing Code: CS-251. Producer or source: Heat Treater's Guide.

SAE 1034, SAE 1035, SAE 1037, CEN C35, ISO C35

Abstract 1034, 1035, 1037, C35, C35E, and C35R are wrought medium-carbon (carbon = 0.32–0.39%) non-alloy steels that are used in the normalized, cold worked, or quenched and tempered condition. 1034, 1035, 1037, C35E, and C35R may also be flame or induction hardened, nitrided, or nitrocarburized. These steels are widely used for small, moderately stressed parts that require higher strength levels than can be achieved by the lower carbon grades, and also for applications where a combination of moderate strength and good toughness is required. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on forming and heat treating. Filing Code: CS-250. Producer or source: Heat Treater's Guide.

SAE 1045, SAE 1045H, SAE 1046, CEN C45, ISO C45

Abstract 1045, 1045H, 1046, C45, C45E, and C45R are wrought medium-carbon (carbon = 0.42–0.51%) non-alloy steels that are used in the normalized, cold worked, or quenched and tempered condition. 1045, 1045H, 1046, C45E, and C45R may also be flame or induction hardened, nitrided, or nitrocarburized. These steels are widely used for moderately and highly stressed parts that require higher strength levels than can be achieved by the lower carbon grades, and where the expense of an alloy steel is not justified. Owing to their low hardenability their use in the quench hardened and tempered condition is not recommended for large sizes as the improvement in mechanical properties over the normalized condition is insufficient to justify the additional cost of heat treatment. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on forming and heat treating. Filing Code: CS-247. Producer or source: Heat Treater's Guide.

SAE 1050, SAE 1053, CEN C50, ISO C50

Abstract 1050, 1053, C50, C50E, and C50R are wrought medium-carbon (carbon = 0.47–0.55%) non-alloy steels that are used in the normalized, cold worked, quenched and tempered, or austempered condition. 1050, 1053, C50E, and C50R may also be flame or induction hardened, nitrided, or nitrocarburized. These steels are widely used for moderately and highly stressed parts that require higher strength levels than can be achieved by the lower carbon grades, and where the expense of an alloy steel is not justified. Owing to their low hardenability, their use in the quench hardened and tempered condition is not recommended for large sizes, as the improvement in mechanical properties over the normalized condition is insufficient to justify the additional cost of heat treatment. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on forming and heat treating. Filing Code: CS-248. Producer or source: Heat Treater's Guide.

SAE 1039, SAE 1040, CEN C40, ISO C40

Abstract 1039, 1040, C40, C40E, and C40R are wrought medium-carbon (carbon = 0.37–0.44%) non-alloy steels that are used in the normalized, cold worked, or quenched and tempered condition. 1039, 1040, C40E, and C40R may also be flame or induction hardened, nitrided, or nitrocarburized. These steels are widely used for moderately and highly stressed parts that require higher strength levels than can be achieved by the lower carbon grades, and where the expense of an alloy steel is not justified. Owing to their low hardenability their use in the quench and tempered condition is not recommended for large sizes, as the improvement in mechanical properties over the normalized condition is insufficient to justify the additional cost of heat treatment. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on forming and heat treating. Filing Code: CS-246. Producer or source: Heat Treater's Guide.

Cybersecurity for Heat Treaters

Abstract This article describes recent U.S. government cybersecurity regulations and their applicability to the heat treating industry. Compliance mitigates the impact of lost or compromised data, secures sensitive information, helps maintain a trustworthy reputation with customers, and helps to avoid the ensuing legal trouble that comes after a cybersecurity breach.

Hardness behavior of W. Nr. 1.7709 steel, oil quenched and tempered between 475°C and 575°C

Steel components frequently involve a heat treatment to improve mechanical properties. In order to meet difficult working conditions, several components are hardened by quenching. W. Nr. 1.7709 is a representative structural steel with very low thermal conductivity among EN wrought alloy steels, which is extensively used after hardening and tempering. Although the steelmakers provide technical information about their heat treatment sequence, the tempering diagram of the specific grade has not been designed yet. The present paper analyses the temper resistance of the specific steel after oil quenching and tempering at high temperatures. Samples of identical chemical compositions were accordingly prepared and randomized. Five groups of ten specimens were austenitized at 960°C, hold for 30 minutes and were quenched in oil. They were tempered for two hours at different temperatures between 475°C and 575°C. Specific temperatures are interesting to the heat treaters, as they could allow certain transformations which take place during tempering. Hardness measurements were carried out and statistically processed. The tempering diagram was plotted to the specified temperature range. The influence of tempering temperature on steel hardness was analysed and the resistance to tempering back of the steel was discussed. The tempering diagram is critical for metallurgists as it represents a guide to define the proper tempering parameters so that the hardness predicted according to the mechanical property requirements are obtained.

Investigation of hardness behavior after carburizing and hardening of 15CrNi6 steel

DIN 15CrNi6 is the most representative grade of the case-hardened steels. The present work analyses the influence of carburizing time on hardness of the specific steel. Specimens with similar chemical composition were heated at 900°C in liquid carbonaceous media for one, two, three and four hours, correspondingly. Then samples were oil quenched and tempered at 180°C for two hours. Microhardness was measured across the carburized zone and case profiles were acquired. The effective case depth was determined as function of carburizing holding time. Core macro hardness was carried out and the impact of holding time on the substrate hardness was discussed. The optimum case depth was defined and the carburizing parameters determined. The hardness control is critical in case hardening practice and results provide practical information to heat treaters, useful both to control the treatment parameters and to minimize the risk of failure.

Effect of Different Surface Conditions on Toughness of Vanadis 6 Cold Work Die Steel-A Review.

The effects of surface roughness, presence of nitrided diffusion regions, and magnetron sputtering of Cr2N–6Ag thin films on the toughness of Cr–V ledeburitic Vanadis 6 die steel were investigated by using the flexural strength measurement method, which was coupled with careful microstructural investigations and analyses of fractured surfaces. The results undoubtedly show that enhanced surface roughness reduces the material toughness, since the cusps formed on the metallic surface as a result of the machining act as preferential sites for crack nucleation and growth. The presence of nitrided regions on the surface, on the other hand, forms a structural notch there, which has a strong detrimental effect on toughness. Deposition of Cr2N–6Ag thin films has only marginal effect on the steel toughness. Practical recommendations for the designers, heat treaters, and coaters of the tools are thus that they should maintain the surface finish quality of the tools as high as possible, avoid too thick and supersaturated nitrided regions, and that there is almost no risk of tool embrittlement due to physical vapor deposition (PVD) coating.

Esquema de control jerárquico para fijación óptima de consignas en un separador trifásico de un tren de tratamiento de crudo

Una de las técnicas para tratar el crudo proveniente de los pozos petroleros es utilizar trenes de tratamiento de crudo para separar las tres fases existentes: gas, petróleo y agua. Uno de los equipos que conforma el tren es el separador trifásico. En este trabajo se demuestra la viabilidad de utilizar un esquema de control jerárquico para la fijación en línea de consignas óptimas de presión y temperatura y así reducir el consumo energético en el tratador térmico. Tal que las variables manipulas y los sets point se encuentren dentro de los límites de la operación segura, con esto se obtienen beneficios económicos y ambientales para esta planta. El logro de esta optimización constituye el aporte principal de este trabajo. Para el desarrollo de este trabajo se diseñó un algoritmo de optimización basado en tres capas jerárquicas en donde la primera capa hace referencia al control directo (PIDs), la segunda capa hace referencia a la optimización de objetivos en estado estacionario (SSTO), la tercera capa hace referencia a la optimización local de objetivos (LSSO). Para la solución a este problema se recurrió a soluciones de optimización lineal y optimización no lineal se relaciona estos algoritmos con el modelo linealizado de la planta, en otros trabajos por lo general se basan en la teoría MPC (Modelo de Control Predictivo). La simulación de los algoritmos se realizó en Matlab y se probaron en una planta simulada en Hysys utilizando el conector Active x server que conecta los dos softwares. En este experimento se logró un ahorro de un 30 % del consumo energético a su vez se encontró que es posible relacionar el modelo de la planta con los algoritmos de optimización lineal y no lineal con lo cual se concluyó que es viable la implementación de estos algoritmos en este tipo de plantas para la optimización de procesos.

Pros and Cons of Various Automotive Materials and Hardening Processes

Abstract Automotive designers and heat treaters have many choices when it comes to the materials and processes that will meet their overall needs. This article reviews some of the major trends affecting automotive heat treating.

Vacuum Heat Treating for Additive Manufacturing

Abstract Heat treaters are discovering new opportunities in the rapidly expanding field of additive manufacturing. This article describes some of the opportunities and challenges for heat treaters in this technology area.

Reducing the Cost of Heat Treating Atmospheres

Abstract Conserving utilities is the simplest, most practical way for heat treaters to reduce costs and remain competitive. This article describes fuel-based nitrogen cogeneration systems that may offer efficiency benefits and reduced emissions for certain heat treating plants.

Evaluation of Quenchant’s Cooling and Hardening Performance

One of the most critical parts of the heat treatment process, and usually the least controllable one, is the quenching operation. Improper selection or application of a quenching medium, or a drift in its cooling characteristics during its lifetime, may result in products that do not meet specifications and therefore give rise to large additional costs to cover e.g. straightening, rework, rejection, delayed deliveries and, sometimes, lost goodwill for the heat treater. In the case of the use of aqueous polymer solutions, the thermo-kinetic parameters characterizing the heat removal capabilities of a quenchant, are variable, in a specific interval with a complex combination of temperatures (T), concentrations (C) and agitation rates (AR). When the direction and degree of change is known, the characteristics of heat removal can be efficiently modified and predicted within given limits. The aim of the work described in this paper is to investigate how the hardening power of Houghton AquaQuench BW-T depends on the complex influence and interaction of T, C and AR.

“Reference QuenchProbe”—An Alternative Probe Design for In-Situ Estimation of Cooling Rates, Heat Flux, and Hardenability During Immersion Quenching of Hardenable Steels

AbstractThis article reviews some of the limitations of the standard cooling curve analysis and the Jominy hardenability test in extending the results to actual quenching in industrial setups and reports the development of a new portable tool—Reference QuenchProbe—for estimating cooling rates, hardness, and microstructure distributions in hardenable steel grades during immersion quenching, which can be used by the heat treater in the plant. The specimen is made of the same grade of steel as the quenched component with section thickness matching that of the component, which is a departure from standard laboratory tests. The test is carried out in the plant under actual conditions dispensing the need to correlate the standard cooling curve data and end quench hardenability tests done in the laboratory to industrial practice. To test the suite of mathematical models associated with the Reference QuenchProbe hardware and software, specimens of different grades of steels were instrumented with a single thermocouple near the surface of the specimen. Using the cooling data at the point of measurement, the cooling rates, microstructure, and hardness at other critical locations were computed. An enthalpy-based non-linear inverse heat conduction model was coupled with austenite decomposition models for handling the latent heat liberated during quenching. Several steels ranging from low carbon to medium alloy steels were both end-quenched by water and immersion quenched in several industrial quenchants. The computed hardness of end quenched and immersion quenched specimens were shown to be in good agreement with the measured values. The Reference QuenchProbe is thus shown to generate data needed for heat treatment process design including quenchant selection, which can be directly used in practice.

Tools for the heat treater – handle with care!

Tools for the heat treater – handle with care!

Modeling of Carbon Concentration Profile Development During Both Atmosphere and Low Pressure Carburizing Processes

Heat treaters need an effective simulation tool to predict the carburization performance of a variety of steels. The tool is needed to not only predict the carbon profile but also optimize the process in terms of the cycle time and the total cost. CarbTool© has been developed to meet these needs for gas and vacuum carburization. In this article, CarbTool© predictions were compared with industrial experimental results for three types of steels (AISI 8620, 5120, and 4320), heat treated by both gas and vacuum carburizing processes. Based on the agreement of model predictions and experimental results, it is found that CarbTool© could be used to predict the carbon concentration profile for a variety of alloys in both gas and vacuum carburizing processes.

A Study of Microstructure and Surface Hardness of Parts Fabricated by Laser Direct Metal Deposition Process

This paper presents an investigation on the microstructure and surface hardness of the parts fabricated by laser assisted Direct Metal Deposition (DMD) technology. A series of engineering metallic alloy powders were used in the DMD process to produce simple 3D geometric structures. The alloy powders investigated include: 316L stainless steel, 420 Stainless Steel, Stellite(R) 6, tool steel (H13), Cholmoloy (Ni Based alloy), and Aluminium Bronze. These were chosen due to their frequent application in engineering parts and components. The microstructure and hardness values have been compared to those of the wrought products (as annealed) as reported in the SAE standards, Heat treater’s guide to metals ASM international, and material data sheets supplied by the materials manufacturers. A significant difference is reported in both hardness and microstructure of the laser deposited samples compared to those of the wrought form.