Effect of Profile Corners on the Nitriding Treatment of AISI H13 Hot Extrusion Dies

2014 ◽  
Vol 136 (2) ◽  
Author(s):  
Syed Sohail Akhtar ◽  
Abul Fazal M. Arif
Keyword(s):  
Nitrogen Concentration ◽  
Hot Extrusion ◽  
Nitride Layer ◽  
Design Guidelines ◽  
H13 Steel ◽  
Extrusion Dies ◽  
Aisi H13 ◽  
Electron Microscopes ◽  
Set Up ◽  
Nitride Layers

One of the utmost challenges of hot aluminum extrusion is to design the die cavities with sharp corners (used to extrude thin-walled profiles) by considering the effective nitriding surface treatment of the die bearing surface in terms of nitride layer uniformity. In the present study, various AISI H13 steel samples (having commonly used profile geometric features) are manufactured using wire electro-discharge machining (EDM) and subsequently nitrided using two-stage controlled nitriding treatment. As a special case, corner features are investigated in terms of compound and nitride layers formation using optical and scanning electron microscopes. Finite element (FE) code abaqus is used to simulate the nitriding process using mass diffusion analysis in line with experimental set up. Both experimental and numerical results are found in close agreement in terms of nitrogen concentration and corresponding microhardness profiles. Some design modifications are implemented in FE code for corner profile features for uniform nitride layer development. In view of the current results, some design guidelines are suggested for effective and uniform nitride layer formation in order to secure high quality extruded product and extended die life.

Experimental and Numerical Investigation of Extrusion Die Profiles for Uniform and Effective Case-Hardening Treatment

2012 ◽  
Author(s):  
Syed Sohail Akhtar ◽  
Abul Fazal M. Arif
Keyword(s):  
Nitrogen Concentration ◽  
Compound Layer ◽  
Nitride Layer ◽  
Case Depth ◽  
Design Guidelines ◽  
Case Hardening ◽  
H13 Steel ◽  
Die Profile ◽  
Aisi H13 ◽  
Electron Microscopes

One of the utmost challenges of hot aluminum extrusion is to design the die cavities, used to extrude thin-walled profiles, by considering the effective nitriding surface treatment of the die bearing surface in terms of nitride layer uniformity. In the present study, various AISI H13 steel samples (having commonly-used profile geometric features) are manufactured using wire EDM and subsequently nitrided using two-stage controlled nitriding treatment. The uniformity and depth of nitride layers formation on these are investigated in terms of compound layer and total nitride case depth using optical and scanning electron microscopes. Finite element code ABAQUS is used to simulate the nitrding process using sequentially coupled thermo-diffusive analysis in line with experimental set up. Both experimental and numerical results are found in close agreement in terms of nitrogen concentration and corresponding micro-hardness profiles. Some design modifications are implemented in FE code for critical die profile features for uniform nitride layer development. In view of the current results, some design guidelines are suggested for effective and uniform nitride layer formation in order to secure high quality extruded product and extended die life.

Prediction of Residual Stresses During Gas Nitriding of H13 Steels Using Phase Field Approach

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Syed Sohail Akhtar ◽  
Abba Abdulhamid Abubakar ◽  
Abul Fazal M. Arif
Keyword(s):  
Residual Stresses ◽  
Phase Field ◽  
Nitrogen Concentration ◽  
Hot Extrusion ◽  
Nitriding Process ◽  
Phase Field Method ◽  
Design Strategies ◽  
Gas Nitriding ◽  
Aisi H13 ◽  
Nitride Layers

Gas nitriding is a common surface treatment practice to improve the wear resistance of AISI H13 hot extrusion die cavities. However, due to the presence of complex and sharp features of die cavities, it has been observed that nonuniform nitride layer develops in these regions. Moreover, the formation of compound layer in the surface vicinity of nitrided surfaces leads to the development of transformation-induced stresses. The present work presents the application of the phase field method in predicting the evolution of the nitride layers and associated residual stresses during the gas nitriding of AISI H13 tool steels. Nitriding process is modeled and simulated in line with experimental setup, which uses automated two-stage controlled nitriding process. Some representative samples having commonly used geometric features are manufactured and nitrided for validation purpose. Both experimental and numerical results are found in close agreement in terms of nitrogen concentration and corresponding microhardness profiles. The results show that high stresses are induced at the surface due to formation of the nitride layers, and these stresses are found to be higher at the sharp corners. In view of the current results, some process and design strategies are suggested for improved and more effective nitriding treatment of hot extrusion dies used in the industry.

Prediction of Transformation-Induced Residual Stresses During Gas Nitriding of H13 Steels Using Phase Field Approach

2014 ◽  
Author(s):  
Syed Sohail Akhtar ◽  
Abba Abdulhamid Abubakar ◽  
Abul Fazal M. Arif
Keyword(s):  
Residual Stresses ◽  
Phase Field ◽  
Nitrogen Concentration ◽  
Hot Extrusion ◽  
Nitriding Process ◽  
Phase Field Method ◽  
Design Strategies ◽  
Gas Nitriding ◽  
Aisi H13 ◽  
Nitride Layers

Gas nitriding is a common surface treatment practice to improve the wear resistance of AISI H13 hot extrusion die cavities. However, due to the presence of complex and sharp features of die cavities, it has been observed that non-uniform nitride layer develops in these regions. Moreover, the formation of compound layer in the surface vicinity of nitrided surfaces leads to the development of transformation-induced stresses. The present work presents the application of the phase field method in predicting the evolution of the nitride layers and associated residual stresses during the gas nitriding of AISI H13 tool steels. Nitriding process is modeled and simulated in line with experimental set-up which uses automated two-stage controlled nitriding process. Some representative samples having commonly used geometric features are manufactured and nitrided for validation purpose. Both experimental and numerical results are found in close agreement in terms of nitrogen concentration and corresponding micro-hardness profiles. The results show that high stresses are induced at the surface due to formation of the nitride layers and these stresses are found to be higher at the sharp corners. In view of the current results, some process and design strategies are suggested for improved and more effective nitriding treatment of hot extrusion dies used in the industry.

Investigation of nitride layers deposited on annealed AISI H13 steel by die-sinking electrical discharge machining

2020 ◽  
Vol 109 (7-8) ◽  
pp. 2325-2336
Author(s):  
Sinval Pedroso da Silva ◽  
Alexandre Mendes Abrão ◽  
Peter Georg Weidler ◽  
Ernane Rodrigues da Silva ◽  
Marcelo Araújo Câmara
Keyword(s):  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
H13 Steel ◽  
Aisi H13 Steel ◽  
Aisi H13 ◽  
Nitride Layers

Die Soldering Phenomenon on the H13 Tool Steel with Shot Peening and Nitriding Surface Treatment

2015 ◽  
Vol 1101 ◽  
pp. 157-163
Author(s):  
Myrna Ariati ◽  
Dwi Marta Nurjaya ◽  
Rizki Aldila
Keyword(s):  
Surface Treatment ◽  
Tool Steel ◽  
Shot Peening ◽  
Surface Hardness ◽  
Nitride Layer ◽  
H13 Steel ◽  
Gas Nitriding ◽  
Aisi H13 Steel ◽  
H13 Tool Steel ◽  
Aisi H13

Die soldering occurs when molten aluminum sticks to the surface of a die material and remains there after the ejection of the part. This resulted in low productivity and economic value in the foundry industry. Nitriding surface treatment is considered as an effective way in enhancing the service life of AISI H13 steel dies and to prevent soldering effect. The focus of this paper is to investigate the influence of three different surface conditions in terms of roughness, gas nitriding and pretreatment prior to gas nitriding on the soldering effect. Three kind of samples made of AISI H13 steel were pretreated (quenched and tempered) and followed by : shot peened, gas nitrided and shot peening followed by gas nitriding, were immersed in liquid melted ADC 12 Aluminium alloy at 30 seconds, 30 minutes, 2 hours and 5 hours, at a constant temperature of 680oC in a holding furnace. Characterizations on the surface of the steel were focused on the optical microstructure, microhardness profile, FE SEM observation and enegy dispersive spectrometry mapping. It was found that shot peening prior to nitriding gives a higher surface hardness and depth of nitride layer of H13 tool steel, 1140 HV (>70 HRC) and 120.5 μm, than the nitriding only process, 1033 HV (68 HRC) and 105 μm. The higher the hardness and depth of nitride layer expected would reduce the die soldering effect at the surface of the H13 tool steel dies. It was also found that the only shot peening treatment resulted in a tendency of soldering accompanied by the formation of intermetallic layers ; while soldering is not found on the nitrided and shot peened-nitrided samples.

Optimum Heat Treatment of Extrusion Die Steel

2014 ◽  
Vol 911 ◽  
pp. 215-219 ◽  
Author(s):  
Sayyad Zahid Qamar
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Hot Extrusion ◽  
Cyclic Process ◽  
H13 Steel ◽  
Tempering Temperature ◽  
Extrusion Dies ◽  
Extrusion Die ◽  
Die Set ◽  
Optimum Heat

Commercial hot extrusion is a billet-by-billet cyclic process, with high thermal and mechanical stresses generated in the die set. The die is a costly piece of equipment, and its long service life is essential for profitable operation. Extrusion dies primarily fail by fracture, wear, and plastic deformation. To avoid early failure, it is essential to have an optimum combination of toughness and hardness in the die. This combination can be achieved through a judicious mix of heat treatment and surface hardening. Experiments were conducted to determine mechanical properties of H13 steel after various heat treatment sequences. Heat treatment strategy is described in detail, and effect of different tempering temperatures on fracture toughness and hardness of the tool steel is reported. Changes in mechanical properties are also related to the variation in microstructure. For use in commercial hot extrusion dies, optimum tempering temperature for H13 steel was found to be near 525-600oC, for the best combination of toughness and hardness.

MUSTANG-LC

Alloy Digest ◽  
1967 ◽  
Vol 16 (4) ◽  
Keyword(s):  
Physical Properties ◽  
High Speed ◽  
High Speed Steel ◽  
Hot Extrusion ◽  
Heat Treating ◽  
Hot Forming ◽  
Steel Company ◽  
Extrusion Dies ◽  
Die Life

Abstract Mustang-LC is a tungsten-molybdenum high-speed steel specially developed for hot work applications requiring long die life. It is recommended for hot forming and swaging dies, hot extrusion dies, hot punches, etc. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, machining, and joining. Filing Code: TS-192. Producer or source: Jessop Steel Company.

UNS T20819

Alloy Digest ◽  
1989 ◽  
Vol 38 (2) ◽  
Keyword(s):  
Elevated Temperatures ◽  
Hot Extrusion ◽  
Heat Treating ◽  
High Toughness ◽  
Extrusion Dies ◽  
Extrusion Die ◽  
Steel Mills ◽  
Temperature Performance ◽  
Heat Checking ◽  
Resistance To Heat

Abstract UNS T20819 is a hot-work tool and die steel that is characterized by excellent resistance to shock and abrasion at elevated temperatures. This steel provides relatively high toughness and outstanding resistance to heat checking and softening at elevated temperatures. Among its many applications are hot-punch tools, forging dies and inserts, brass extrusion dies, permanent molds for brass casting and hot-extrusion die inserts for steel. This datasheet provides information on composition, hardness, and tensile properties as well as fracture toughness. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: TS-496. Producer or source: Tool steel mills.

scholarly journals Influence of Deposition Patterns on Distortion of H13 Steel by Wire-Arc Additive Manufacturing

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 485
Author(s):  
Xufeng Li ◽  
Jian Lin ◽  
Zhidong Xia ◽  
Yongqiang Zhang ◽  
Hanguang Fu
Keyword(s):  
Additive Manufacturing ◽  
Temperature History ◽  
H13 Steel ◽  
Deposition Patterns ◽  
Field Distortion ◽  
Set Up ◽  
Manufacturing Technologies ◽  
Inherent Strain ◽  
Inherent Strain Method ◽  
Wire Arc Additive Manufacturing

Wire-arc additive manufacturing (WAAM) has been considered as one of the potential additive-manufacturing technologies to fabricate large components. However, its industrial application is still limited by the existence of stress and distortion. During the process of WAAM, the scanning pattern has an important influence on the temperature field, distortion and final quality of the part. Four kinds of deposition patterns, including sequence, symmetry, in–out and out–in, were designed to deposit H13 steel in this study. An in situ measurement system was set up to record the temperature history and the progress of accumulated distortion of the parts during deposition. An S value was proposed to evaluate the distortion of the substrate. It was shown that the distortion of the part deposited by sequence was significantly larger than those of other parts. The distortion deposited by the out–in pattern decreased by 68.6% compared with sequence. The inherent strain method and strain parameter were introduced to expose the mechanism of distortion reduction caused by pattern variation.

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