Microstructure and Anisotropy of Plastic Properties of Thermomechanically-Processed HSLA-Type Steel Plates

Abstract

The paper presents the investigation results of the impact of shear bands on microstructure, mechanical properties, and anisotropy of plastic properties of HSLA (high-strength, low-alloy) type steel plates, produced in the process of thermomechanical rolling. A lack of conditions ensuring the complete static recrystallization between successive roll passes leads to localization of plastic deformation and formation of shear bands in dynamically-recrystallized austenite enriched with carbon and other interstitial elements, which transform into carbide segregation bands during tempering. These bands are the cause of low impact resistance of rolled plates, especially in the transverse direction, and the high degree of anisotropy of plastic properties in the plates. formation of shear bands in the austenite in the direction of rolling [18][19][20]. These bands may cause the anisotropy of plastic properties in the plates and decrease their impact toughness [21-23]. Materials and MethodsThe tests were carried out on low-carbon toughened steel. The chemical composition is shown in Table 1. The requirements for weldable plates are: YS > 960 MPa and a ductile-brittle transition temperature T 45J equal to −40 • C. The carbon equivalent of this steel, calculated on its chemical composition, is equal to C E = 0.55. The steel is characterized by high metallurgical cleanliness, associated with low content of P and S.

Effect of Heat Treatment Conditions on Corrosion Resistance of 0.28C–1.4Mn–0.3Si–0.26Cr Steel with Nb, Ti, and V Microadditions

“…Modern constructional steels should be characterized not only by high strength, crack resistance, good weldability, and formability, but also low weight and guaranteed service life of the constructions made of these steels. The HSLA-type steels, usually containing up to about 0.2% C and about 1.5% Mn as well as microadditions with high chemical affinity for carbon and nitrogen (Nb, Ti, and V up to 0.1%), sometimes with increased concentration of N, and in the case of toughening steel also up to 0.005% B-increasing hardenability, broadly meet the mentioned requirements [9][10][11][12][13][14]. The HSLA-type steels are widely used in many industries due to their high strength-to-weight ratio and high ductility at low production costs.…”

The Effect of Cooling Rate on the Microstructure Evolution and Mechanical Properties of Ti-Microalloyed Steel Plates

“…Based on the above problem, new generation TMCP (NG-TMCP), that is TMCP involving ultrafast cooling (UFC) technology, is currently being applied to industrial production [19][20][21], aiming to reduce the consumption of expensive alloying elements, improve the homogeneity of the steel plate, and make the steel making process economically visible [15,[22][23][24]. The cooling medium for UFC is water, and the finish cooling temperature was controlled by changing the pressure and density of the water outlet, which was determined by the automatic control system.…”

Thermodynamic Analysis of Precipitation Process of Complex Carbonitride TixV1-xCyN1-y in HSLA-Type Steel

“…The increasing requirements of the recipients of steel products determine the necessity to produce grades of high strength, guaranteed ductility, susceptibility to technological deformations in cold and hot conditions, and limited anisotropy of plastic properties [1][2][3][4][5]. The simultaneous fulfi llment of these opposing properties requires a rational selection of the chemical composition, ensuring the desired hardenability and weldability of the steel [6][7][8][9][10][11].…”