scholarly journals Steel with control austenitic transformation during operation

2021 ◽  
Vol 98 (2) ◽  
pp. 47-53
Author(s):  
O. M. Sydorchuk ◽  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Service Life ◽  
Industrial Test ◽  
Tempering Temperature ◽  
Austenitic Transformation ◽  
Wide Range ◽  
Copper Nickel Alloy ◽  
Treatment Structure ◽  
First Time

The intermediate class of steels, which at room temperature belong to the ferritic state, and at operating temperature pass into the austenitic region, are called steels with control of austenitic transformation during operation. The possibility of increasing the service life of such intermediate steels at high temperatures (above the critical point A3) is shown. For the first time, the cast structure and phase-structural state of steel (grade 4Kh3N5М3F) obtained by electroslag remelting were studied. An improved composition of steel (4Kh4N5М3F) for the production of stamping tools for hot pressing of copper, copper and aluminum alloys is proposed. When setting the critical points (A1 and A3) of the investigated steel, which was confirmed by the results of high-temperature X-ray phase analysis, it was possible to optimize the heat treatment (annealing) of steel 4Kh3N5M3F and 4Kh4N5M4F2 in cast and forged condition, which facilitated processing tool. The results of researches on optimization of modes of heat treatment (hardening, tempering) of steel are given. The mechanical properties (strength, toughness, heat resistance) of steel in cast and forged state depending on the tempering and tempering temperature are determined. The tempering brittleness of the experimental steel is determined. An experimental-industrial test of a stamping tool (die dies, extruder parts) made of the investigated steel was carried out. The possibility of using stamped steel with adjustable austenitic transformation for a wide range of operating temperatures of hot deformation of aluminum alloy AK7h (450-500 ºC), copper M1 (600-630 ºC) and copper-nickel alloy MNZh 5-1 (900-950 ºC) with increased service life in comparison with steels of ferrite class 4Kh5МF1S and 3Kh3М3F. Keywords: die steel, composition, thermal treatment, structure, mechanical properties.

scholarly journals INFLUENCE OF HEAT TREATMENT ON DIE STEEL 4Kh4N5М4F2 AND ESTABLISHMENT OF ITS PHYSICAL AND MECHANICAL PROPERTIES

2021 ◽  
pp. 34-38
Author(s):  
Oleh Sydorchuk
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Electrical Conductivity ◽  
Service Life ◽  
Impact Strength ◽  
Cast Steel ◽  
Hardened Steel ◽  
Specific Electrical Conductivity ◽  
Tempering Temperature ◽  
Temperature Mode

The results of researches after heat treatment (hardening and tempering) of alloyed structural steel of grade 4Kh4N5М4F2 in cast and forged state are given. It is recommended to carry out partial recrystallization (incomplete annealing) of the experimental steel (4Kh4N5М4F2) at a temperature of 750±20 °С. It is recommended to carry out thermo-deformation treatment (forging at a temperature of 1170±20 °C), which doubled the grain yield of hardened steel and increased the toughness five times after tempering. The optimal temperature mode of hardening (1095±5 °С) of cast and forged steel, the hardness of which coincides at the level of 56 HRC, is established. The grain score in cast and forged state (№ 3–№ 6 and № 6–№ 8, respectively) of the investigated steel depending on the quenching temperature (1050–1110 °С) is shown. The dependence between hardness and specific electrical conductivity of steel after hardening in comparison with cast and forged state is established. It is established that at optimized modes of heat treatment of the investigated steel it was determined by the minimum value of the parameter – specific electrical conductivity. Thus, for the optimal value of the tempering temperature of steel (1095 ºC), the specific electrical conductivity was 0,075 Ohm•mm2/ m, and at tempering (595 ºC) – 0,0415 Ohm•mm2/m. The methodical approach after hardening of steel is offered that allows carrying out control of a temperature mode at heating of the stamp tool. It is established that after hardening of steel, forged has the highest conductivity than cast. Physico-mechanical properties (strength threshold, impact strength, hardness, microhardness in the metal structure and specific electrical conductivity) of the investigated hardened steel (cast and forged) after tempering are presented. An increase in the hardness and strength of cast steel during tempering at temperatures from 450 to 500 °C, which is provided by the release of the carbide component, where there is an intensive increase in microhardness. It was found that the tempering brittleness of the investigated steel at a temperature of 475±15 °C. An anomalous decrease in impact strength (up to 15 J/cm2) and an intensive increase in the specific electrical conductivity of cast and forged steel at tempering brittleness are shown. The increase of microhardness of the investigated steel is established, which promotes increase of wear resistance and increase of service life of the stamping tool. It is established that during reheating (tempering), the conductivity in steel increases, and the structurally sensitive mechanical characteristic (impact strength) changes intensively, which increases twice in the range of tempering brittleness temperatures of 475±15 ºС. This makes it possible to increase the service life of the press tool (die) made of steel 4Kh4N5M4F2 for hot deformation of aluminum alloy in the temperature range 450-500 °C.

Comparative Study on Tempering Response of Martensitic Grade AISI-420 Stainless Steels with Varying Carbon Content

2012 ◽  
Vol 710 ◽  
pp. 489-494 ◽  
Author(s):  
Anil Kumar ◽  
Rohit Kumar Gupta ◽  
M.K. Karthikeyan ◽  
P. Ram Kumar ◽  
Parameshwar Prasad Sinha
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Stainless Steel ◽  
Carbon Content ◽  
Stainless Steels ◽  
Temper Embrittlement ◽  
Tempering Temperature ◽  
Aisi 420 ◽  
Wide Range ◽  
Structural Applications

Martensitic grade stainless steels are being extensively used in aerospace, defence and nuclear sectors for structural applications. Specialized applications require close control in chemistry and heat treatment parameters. Control of carbon in AISI-420, alloying content has typical service advantages. To study the effect of tempering temperature with carbon content on mechanical properties, various heat treatment cycles were devised, avoiding the regime of temper embrittlement. This paper presents the tempering response of medium carbon stainless steel AISI-420 grade with respect to change in carbon content from 0.2% to 0.3%. It is observed that, by varying the tempering temperature, the grade can be tailored to obtain wide range of mechanical properties. With increasing carbon content, martensite is found to be changing in morphology from lath to lath & plate (mixed) and the amount of retained austenite also increases. An attempt has been also made to arrive at a structure-property correlation in this grade of stainless steel.

Effect of Different Heat Treatments on Mechanical Properties of Laser Sintered Additive Manufactured Parts

2017 ◽  
Author(s):  
Sagar Sarkar ◽  
Cheruvu Siva Kumar ◽  
Ashish Kumar Nath
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Yield Strength ◽  
Tensile Strain ◽  
Wear Loss ◽  
Layer By Layer ◽  
Solution Annealing ◽  
Wear Properties ◽  
Sem Images ◽  
Wide Range

One of the most popular additive manufacturing processes is laser based direct metal laser sintering process which enables us to make complex three dimensional parts directly from CAD models. Due to layer by layer formation, parts built in this process tend to be anisotropic in nature. Suitable heat treatment can reduce this anisotropic behaviour by changing the microstructure. Depending upon the applications, a wide range of mechanical properties can be achieved between 482–621° C temperature for precipitation-hardened stainless steels. In the present study effect of different heat treatment processes, namely solution annealing, ageing and overaging, on tensile strength, hardness and wear properties has been studied in detail. Suitable metallurgical and mechanical characterization techniques have been applied wherever required, to support the experimental observations. Results show H900 condition gives highest yield strength and lowest tensile strain at break whereas solution annealing gives lowest yield strength and as-built condition gives highest tensile strain at break. SEM images show that H900 and H1150 condition produces brittle and ductile morphology respectively which in turn gives highest and lowest hardness value respectively.XRD analysis shows presence of austenite phases which can increase hardness at the cost of ductility. Average wear loss for H900 condition is highest whereas it is lowest for solution annealed condition. Further optical and SEM images have been taken to understand the basic wear mechanism involved.

RAFFMETAL EN AB-Al Si7Mg0.3 (EN AB-42100)

Alloy Digest ◽  
2021 ◽  
Vol 70 (9) ◽  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Corrosion Resistance ◽  
High Strength ◽  
Heat Treating ◽  
Magnesium Content ◽  
Casting Alloy ◽  
Permanent Mold ◽  
Good Corrosion Resistance ◽  
Wide Range

Abstract Raffmetal EN AB-Al Si7Mg0.3 (EN AB-42100) is a heat-treatable, Al-Si-Mg casting alloy in ingot form for remelting. It is used extensively for producing sand, permanent mold and investment castings for applications requiring a combination of excellent casting characteristics, high strength with good elongation, and good corrosion resistance. This alloy can be produced to a wide range of mechanical properties by making small adjustments to the magnesium content and/or heat treatment. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Al-480. Producer or source: Raffmetal S.p.A.

Microstructure and Mechanical Properties of High Strength Alloyed Steel for Aerospace Application

2018 ◽  
Vol 284 ◽  
pp. 351-356 ◽  
Author(s):  
Mikhail V. Maisuradze ◽  
Maksim A. Ryzhkov
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
High Strength ◽  
Single Stage ◽  
The Novel ◽  
Tempering Temperature ◽  
Quenching And Partitioning ◽  
Aerospace Application ◽  
Cooling Conditions ◽  
Quenching And Tempering

The high strength aerospace steel alloyed with Cr, Mn, Si, Ni, W and Mo was studied. The austenite transformations under continuous cooling conditions were investigated using the dilatometer analysis at the cooling rates 0.1...30 °C/s. The mechanical properties of the studied steel were determined after the conventional quenching and tempering heat treatment. The dependences of the mechanical properties on the tempering temperature were obtained. The novel quenching and partitioning heat treatment was applied to the steel under consideration. The microstructure and the mechanical properties were studied after three different modes of the quenching and partitioning (QP) treatment: single-stage QP, two-stage QP and single-stage QP with subsequent tempering (QPT).

scholarly journals Synthesis, Characterization and Mechanical Properties of Nanocomposites Based on Novel Carbon Nanowires and Polystyrene

2020 ◽  
Vol 10 (17) ◽  
pp. 5737
Author(s):  
Vasilis Kostas ◽  
Maria Baikousi ◽  
Nektaria-Marianthi Barkoula ◽  
Aris Giannakas ◽  
Antonios Kouloumpis ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Analytical Techniques ◽  
Polymer Nanocomposite ◽  
Precipitation Method ◽  
Templating Method ◽  
Polymer Properties ◽  
Wide Range ◽  
First Time ◽  
Range Of Values ◽  
Carbon Nanowires

Carbon into polymer nanocomposite is so far a common additive for the enhancement of the polymer properties. The properties of the polymer, such as thermal, and especially its mechanical properties, are improved by the homogeneously dispersed carbon nanoparticles on the polymer matrix. In this study, carbon wires in nano dimensions are, for the very first time, synthesized via the hard templating method from the silicate matrix MCM-41, and used as nano additives of polystyrene. The carbon nanowires were chemically oxidized, and further modified by attaching octadecylamine molecules, for the development of organic functionalities onto carbon nanowires surface. The nanocomposite materials of polystyrene with the modified carbon nanowires were prepared by a solution-precipitation method at three nano additive to polymer loadings (1, 3 and 5 wt%). The as-derived nanocomposites were studied with a combination of characterization and analytical techniques. The results showed that the thermal and mechanical properties of the polystyrene nanocomposites gradually improved while increasing nano-additive loading until 3 wt%. More specifically, the 3 wt% loading sample showed the best mechanical properties, while the 5 wt% sample was difficult to achieve satisfactory dispersion of carbon nanowires and consequently has a wide range of values.

Weldability Investigation of Temper-Grade Steels

2008 ◽  
Vol 589 ◽  
pp. 31-35
Author(s):  
Gábor Lengyel ◽  
Béla Palotás
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Heat Conduction ◽  
Heat Affected Zone ◽  
Three Dimensional ◽  
Cold Cracking ◽  
Crucial Importance ◽  
Preheat Temperature ◽  
Wide Range

The mechanical properties of temper-grade steels can be modified in a wide range by heat treatment. The principle of heat treatment lies in the good hardenability, so when such steels are welded it is very likely that the heat affected zone is hardened. Considering the fact that in the case of design simplifications it may be needed to weld temper-grade steels, as well therefore it is of crucial importance to eliminate cold cracking. There are many methods available to determine preheat temperature. The applicability of methods for determination of preheat temperature was checked by experimental welding for both two and three dimensional heat conduction. According to our experience the different methods cannot be applied in general namely they are valid only under certain conditions.

Effects of Tempering Temperature and Heat-Treatment Path on the Microstructural and Mechanical Properties of ASTM Gr.92 Steel

2010 ◽  
Vol 48 (1) ◽  
pp. 28-39
Author(s):  
Yeon-Keun Kim ◽  
Chang-Hee Han ◽  
Jong-Hyuk Baek ◽  
Sung-Ho Kim ◽  
Chan-Bock Lee ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tempering Temperature

Mechanical Properties of a Mild-Alloy Steel for Aerospace Engineering

2021 ◽  
Vol 410 ◽  
pp. 221-226
Author(s):  
Mikhail V. Maisuradze ◽  
Maxim A. Ryzhkov ◽  
Dmitriy I. Lebedev
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
High Strength ◽  
Aerospace Engineering ◽  
Isothermal Heat Treatment ◽  
Tempering Temperature ◽  
Optimal Heat Treatment ◽  
Treatment Conditions ◽  
Quenching And Tempering ◽  
Conventional Oil

The features of microstructure and mechanical properties of the aerospace high strength steel were studied after the implementation of various heat treatment modes: conventional oil quenching and tempering, quenching-partitioning, austempering. The dependence of the mechanical properties on the tempering temperature was determined. The basic patterns of the formation of mechanical properties during the implementation of isothermal heat treatment were considered. The optimal heat treatment conditions for the studied steel were established.

Effect of Different Heat Treatments on Mechanical Properties of Laser Sintered Additive Manufactured Parts

2017 ◽  
Vol 139 (11) ◽  
Author(s):  
Sagar Sarkar ◽  
Cheruvu Siva Kumar ◽  
Ashish Kumar Nath
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Yield Strength ◽  
Computer Aided Design ◽  
Tensile Strain ◽  
Wear Loss ◽  
Layer By Layer ◽  
Solution Annealing ◽  
Sem Images ◽  
Wide Range

One of the most popular additive manufacturing processes is laser-based direct metal laser sintering (DMLS) process, which enables us to make complex three-dimensional (3D) parts directly from computer-aided design models. Due to layer-by-layer formation, parts built in this process tend to be anisotropic in nature. Suitable heat treatment can reduce this anisotropic behavior by changing the microstructure. Depending upon the applications, a wide range of mechanical properties can be achieved between 482 °C and 621 °C temperature for precipitation-hardened stainless steels. In the present study, effect of different heat treatment processes, namely solution annealing, aging, and overaging, on tensile strength, hardness, and wear properties has been studied in detail. Suitable metallurgical and mechanical characterization techniques have been applied wherever required, to support the experimental observations. Results show H900 condition gives highest yield strength and lowest tensile strain at break, whereas solution annealing gives lowest yield strength and as-built condition gives highest tensile strain at break. Scanning electron microscope (SEM) images show that H900 and H1150 condition produces brittle and ductile morphology, respectively, which in turn gives highest and lowest hardness value, respectively. X-ray diffraction (XRD) analysis shows presence of austenite phases, which can increase ductility at the cost of hardness. Average wear loss for H900 condition is highest, whereas it is lowest for solution annealed condition. Further optical and SEM images have been taken to understand the basic wear mechanism involved.

Sign in / Sign up

Export Citation Format

Share Document