The Influence of Quenching Temperature on the Structure of a Dual-Phase Steel with 0.094% C and 0.53% Mn

2015 ◽  
Vol 809-810 ◽  
pp. 507-512 ◽  
Author(s):  
Constantin Dulucheanu ◽  
Nicolai Bancescu ◽  
Traian Severin

In this article, the authors have analysed the influence of quenching temperature (TQ) on the microstructure of a dual-phase steel with a low carbon and manganese content (0,094 % C and 0,53 % Mn). The ferrite-martensite structures, typical of the dual-phase steels, has been obtained by intercritical quenching that consisted of heating at temperatures (TQ) ranging between 750 °C and 830 °C, maintaining for 30 minutes and cooling in water. After carrying out intercritical heat treatments, samples have been subjected to metallographic analysis through which the volume fraction of martensite (VM), the volume fraction of ferrite (VF), the carbon content of the martensite (CM), the morphology and distribution of these phases have been determined, and then, the influence of quenching temperature (TQ) has been established.

2015 ◽  
Vol 808 ◽  
pp. 28-33 ◽  
Author(s):  
Constantin Dulucheanu ◽  
Nicolai Bancescu ◽  
Traian Severin

In this article, the authors have analysed the influence of quenching temperature (TQ) on the mechanical properties of a dual-phase steel with 0.094 % C and 0.53% Mn. In order to obtain a ferrite-martensite structure, specimens of this material have been the subjected to intercritical quenching that consisted of heating at 750, 770, 790, 810 and 830 °C, maintaining for 30 minutes and cooling in water. These specimens have then been subjected to metallographic analysis and tensile test in order to determine the volume fraction of martensite (VM) in the structure, ultimate tensile strength (Rm), the 0.2% offset yield strength (Rp0.2), the total elongation (A5) and the Rp0.2/Rm ratio.


2020 ◽  
Vol 44 (6) ◽  
pp. 381-386
Author(s):  
Walid Laroui ◽  
Redouane Chegroune ◽  
Şükrü Talaş ◽  
Mourad Keddam ◽  
Riad Badji

Dual Phase steels are widely used in industry for various reasons for their improved mechanical properties owing to their ferrite and martensite contents in microstructure and good formability at industrial scale to achieve final shape with good ductility. In this study, shielded metal arc welding experiments were performed in order to evaluate the metallurgically and mechanically the properties of Dual Phase steels obtained from plain carbon steel AISI 1010 by water quenching at intercritical temperatures. Martensite volume fraction (MVF) was related to the intercritical quenching temperature which defines the mechanical properties of Dual Phase steel. All the welding parameters were kept constant in order to get a value of heat input equals 1.37 KJ/mm for all weldments. Martensite was found to be predominated in the fusion zone and its hardness was the highest compared to base metal (BM) and heat affected zone (HAZ). The extent of ductile zone was found to be dependent on the MVF and reached over 1.2 mm wide. Tensile properties of weldments were deteriorated by 35% in ultimate tensile strength (UTS) and by 15% in elongation. The failure of all the welded joints was occurred in the SC zone, with the fractured surfaces of a dimple feature.


2020 ◽  
Vol 15 (55) ◽  
Author(s):  
B Sunil ◽  
S. Rajanna

The main aim of the research work is to examine the fracture toughness of the dual phase steels prepared using the intermediate quenching method. The ferrite-martensite dual phase (DP) steel is produced using low carbon micro alloyed steel by the heat treatment and intercritical quenching technique using various intercritical temperatures such as 740,760,780,800 and 820oC. The samples of the produced dual phase steel are analyzed for their microstructure using optical microscope. The fracture toughness investigations for the dual phase steel have been carried out using ASTM standard testing procedure. From the results it is observed that the fine distribution and equal volume fraction of ferrite and martensite phases at 780oC. The effect of which, the A780 steel has demonstrated excellent fracture toughness which is the result of intermediate quenching technique. The fractography analysis it is clear that the ductile initiated brittle fracture is occurred which is due to the increased hard martensite phase and the increment in the stress accumulation at the ferrite which also leads to the higher elongation.


2006 ◽  
Vol 15-17 ◽  
pp. 774-779 ◽  
Author(s):  
M. Mazinani ◽  
Warren J. Poole

The deformation behaviour of martensite and its effect on tensile properties of a lowcarbon dual-phase (DP) steel were investigated. DP steel samples with different martensite contents and morphologies were produced after intercritical annealing at different temperatures using low and high heating rates. Two distinct martensite morphologies were obtained for low and high heating rates. The investigated steel showed the unusual results that the true fracture stress and strain were found to increase with the martensite volume fraction. The plastic deformation of martensite was considered to be responsible for these results. Experimentally, it was observed that the martensite in DP steels with greater than 25-30% martensite can deform plastically during tensile straining. Finally, the effect of tempering on the martensite plasticity was also evaluated. It was found that the tempering process and an increase in the martensite content have a similar effect on promoting martensite plasticity.


2014 ◽  
Vol 788 ◽  
pp. 384-389
Author(s):  
Xin Jun Shen ◽  
Xiang Jun Zhang ◽  
Feng Qin Ji ◽  
Jun Chen ◽  
Shuai Tang ◽  
...  

With the development of auto industry, the F/B dual phase steels were widely used in wheel and underpan due to their lower cost and higher hole expansion property. In the present investigation, the effects of the finishing rolling temperature and initial cooling temperature of ultra fast cooling (UFC) on microstructure and hole expansion property of a low carbon C-Mn steel were investigated using optical microscope (OM) and scanning electron microscope (SEM). It has been found that lowering the finishing rolling temperature can refine the microstructure and the volume fraction of ferrite is increased as the initial cooling temperature of UFC is lowered. Furthermore, both lowering the finishing rolling temperature and the initial cooling temperature of UFC can improve hole expansion property.


2005 ◽  
Vol 500-501 ◽  
pp. 639-646
Author(s):  
Aurélie Hug-Amalric ◽  
Xavier Kleber ◽  
Jacques Merlin ◽  
Hélène Petitgand

Magnetic Barkhausen noise measurements have been carried out to characterize ferritemartensite duplex microstructures and industrial Dual-Phase steels. We have first studied ferritemartensite duplex steels, for which the volume fraction and the carbon content of martensite were higher than for industrial Dual-Phase steels. We found linear evolutions between ferrite peak parameters and its proportion. We applied these results to industrial Dual-Phase steels and show that Barkhausen noise measurement can be successfully used for Dual-Phase steels characterization, and in particular for assessment of ferrite proportion.


Sign in / Sign up

Export Citation Format

Share Document