These steels possessed ferrite and martensite structures. The pretempering treatment was applied on two different kinds of steels, i.e., quenched and partitioned steels. Steel was found to be hardened due to the presence of retained austenite. High hardness was reported on the tool steel after applying heat treatment methods. In an experiment, H13 hot worked tool steel was heat-treated in three different conditions, i.e., (a) after tempering (b) while quenching and (c) while tempering. The toughness was reported high at the heat-affected zone of heat-treated samples. They concluded that there was a minor influence of heat treatment on the welding of this steel. They used five different conditions: only preheating, pre and postheating, only postheating, and without pre- or postheating. conducted multipass welding of HSLA-80 steel by using a coated electrode. noticed that the heat-affected zone (with fine-grained structure) possessed higher fatigue strength than that of fusion line and weld metal zone. PWHT is conducted to achieve stability in metallurgical structure and to increase service life of the steel. Here, some of the previous research works are summarized as follows. Still, in the view of production economy and wide application of the steel, continuous research is necessary. This research work has been taken into consideration by many researchers in the last two decades. Īnalysis of postweld heat-treated plates is not a new development.

Įlements included (approximately in weight %) in 1020 steel. These defects begin to remove as soon as recrystallization starts in the γ-austenite zone. Other defects such as strain hardening due to improper cooling can also be generated in the welded joint. Therefore, there is always a chance of formation of residual stresses in the heat-affected zone and welded zone. As the welded zone is suddenly converted into liquid state, a lot of thermal gradients is produced on the other parts of the welded plate. The fusion welding process imparts a complex cooling and solidification phenomena. In addition, the annealing heat treatment technique is adopted to remove the internal stresses in the steel specially in welded joint. Heat treatment can reform the properties of the metal as per the requirement. The most important characteristic of the steel is to change the mechanical properties according to various heating and cooling methods. Some important properties and ingredients of 1020 steel are written in Tables 1 and 2. Hence, the carbon content varies between 0.1 and 0.2%. This grade comes under low carbon steel category. AISI 1020 steel possesses an ideal combination of formability, weldability, and machinability. In such grades, AISI 1020 is very common and is extensively used for construction, fabrication, and manufacturing of different products such as angle, channel, bars, slabs, and sheets. Different grades of steels are used for different working conditions. Steel is one of the highly demanded metals all over the world. A significant refinement into all the mechanical properties was achieved in this work. All the mechanical properties are in good corroboration with microstructure. A clear vision of ferrite, cementite, and martensite on various heat-treated samples made this study important.

Pearlite (coarse and fine) and martensite were the main microstructural findings in the study. Furthermore, a good combination of strength, hardness, and ductility was reported in oil-cooled sample. The sand-cooled sample possessed the highest toughness, whereas water-quenched samples were found to be highly hard. Oil-cooled sample showed a remarkable enhancement in tensile strength. Significant variations in tensile strength and hardness were reported when compared with each other. The tensile strength, impact strength, hardness, and the microstructural attributes were analysed in four welded samples after heat treatment. For analysing mechanical behaviour of all the plates, standard-shaped specimens were prepared out of them. Hence, there were four different samples according to their physical conditions: sand-cooled, water-quenched, oil-quenched, and air-cooled. Different cooling media such as sand, water, oil, and air were used to cool the samples. The heating temperature and holding time were selected as 1040☌ and 60 minutes, respectively. Four pairs of such steel were taken and welded to form four joints. The purpose of this work is to heat the welded samples uniformly so that a possible formation of austenite can be obtained, and hence, residual stresses, if any, can be recovered. This paper presents analysis and comparison into mechanical behaviour and microstructural attributes of postweld heat-treated AISI 1020 (0.21%-C) plates joined by the shielded metal arc welding (SMAW) process.

Engineering curve aisi 1020 table test