The influence of a high aluminium addition on the strength and impact behaviour of hot-rolled Nb containing steels

Novel alloys with high aluminium addition have been developed recently for the new concepts of δ-TRIP, δ-QP and some other high-aluminium low-density steels. The aluminium addition dramatically affects the thermodynamics and kinetics of the formation of austenite. In the present study, the effect of aluminium on the initial microstructure of ferrite and pearlite has been investigated. The equilibrium prediction of phase fraction by thermodynamics calculations is in accordance with the measured austenite fraction during isothermal at intercritical temperature range; both results strongly demonstrate a significant influence of aluminium addition on intercritical region. The isothermal transformation of high aluminium steel during intercritical annealing was delayed, which has an instruction for process design of the industrial continuous annealing and galvanization. The austenite formation during heating in intercritical region was also obviously affected by aluminium addition. The transformation kinetics simulation conducted by DICTRA simulation, as well as the experimental results of dilatometry, indicate a delayed austenite transformation during heating process.

Download Full-text

Further insights on compositional control and heat treatment for improving the impact behaviour of hot-rolled steels containing Nb and Al

Materials & Design ◽

10.1016/j.matdes.2020.108601 ◽

2020 ◽

Vol 190 ◽

pp. 108601 ◽

Cited By ~ 1

Author(s):

Barrie Mintz ◽

Abdullah Qaban ◽

Sumsun Naher

Keyword(s):

Heat Treatment ◽

Impact Behaviour ◽

Hot Rolled ◽

The Impact ◽

Compositional Control

Download Full-text

Observations on the structure at the transformation interface of pearlite in steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100174138 ◽

1990 ◽

Vol 48 (4) ◽

pp. 200-201

Author(s):

F. A. Khalid ◽

D. V. Edmonds

Keyword(s):

Room Temperature ◽

Thin Foil ◽

Carbon Steels ◽

Model Alloy ◽

Growth Interface ◽

Medium Carbon ◽

Solution Treated ◽

Medium Carbon Steels ◽

Alloy Carbide ◽

Hot Rolled

The austenite/pearlite growth interface in a model alloy steel (Fe-1 lMn-0.8C nominal wt%) is being investigated. In this particular alloy pearlite nodules can be grown isothermally in austenite that remains stable at room temperature, thus facilitating examination of the transformation interfaces. This study presents preliminary results of thin foil TEM of the austenite/pearlite interface, as part of a programme of aimed at studying alloy carbide precipitation reactions at this interface which can result in significant strengthening of microalloyed low- and medium- carbon steels L Similar studies of interface structure, made on a partially decomposed high- Mn austenitic alloy, have been reported recently.The experimental alloys were made as 50 g argon arc melts using high purity materials and homogenised. Samples were hot- rolled, swaged and machined to 3mm diameter rod, solution treated at 1300 °C for 1 hr and WQ. Specimens were then solutionised between 1250 °C and 1000 °C and isothermally transformed between 610 °C and 550 °C for 10-18 hr and WQ.

Download Full-text

Ballistic impact behaviour of some ceramics in different environments

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:19948103 ◽

1994 ◽

Vol 04 (C8) ◽

pp. C8-677-C8-682

Author(s):

H.-J. Ernst ◽

K. Hoog ◽

V. Wiesner

Keyword(s):

Ballistic Impact ◽

Impact Behaviour

Download Full-text

Development of trimming technology for hot rolled ultra-low carbon steel

Revue de Métallurgie ◽

10.1051/metal/199390070917 ◽

1993 ◽

Vol 90 (7-8) ◽

pp. 917-922

Author(s):

Y. Matsuda ◽

M. Nishino ◽

J. Ikeda

Keyword(s):

Carbon Steel ◽

Low Carbon Steel ◽

Low Carbon ◽

Ultra Low Carbon Steel ◽

Hot Rolled

Download Full-text

Investigation on the control of multiphase flow behavior in a continuous casting tundish during ladle change

Metallurgical Research & Technology ◽

10.1051/metal/2020070 ◽

2020 ◽

Vol 117 (6) ◽

pp. 619

Author(s):

Rui Xu ◽

Haitao Ling ◽

Haijun Wang ◽

Lizhong Chang ◽

Shengtao Qiu

Keyword(s):

Multiphase Flow ◽

Flow Behavior ◽

Rolled Strip ◽

Impact Zone ◽

Steel Cleanliness ◽

Carry Over ◽

Slag Carry Over ◽

Hot Rolled ◽

Turbulence Inhibitor ◽

The Impact

The transient multiphase flow behavior in a single-strand tundish during ladle change was studied using physical modeling. The water and silicon oil were employed to simulate the liquid steel and slag. The effect of the turbulence inhibitor on the slag entrainment and the steel exposure during ladle change were evaluated and discussed. The effect of the slag carry-over on the water-oil-air flow was also analyzed. For the original tundish, the top oil phase in the impact zone was continuously dragged into the tundish bath and opened during ladle change, forming an emulsification phenomenon. By decreasing the liquid velocities in the upper part of the impact zone, the turbulence inhibitor decreased considerably the amount of entrained slag and the steel exposure during ladle change, thereby eliminating the emulsification phenomenon. Furthermore, the use of the TI-2 effectively lowered the effect of the slag carry-over on the steel cleanliness by controlling the movement of slag droplets. The results from industrial trials indicated that the application of the TI-2 reduced considerably the number of linear inclusions caused by ladle change in hot-rolled strip coils.

Download Full-text