Continuous Casting of Advanced Steels of Near-Peritectic Composition

2010 ◽  
Vol 654-656 ◽  
pp. 17-22 ◽  
Author(s):  
Rian J. Dippenaar
Keyword(s):  
Continuous Casting ◽  
Phase Transformations ◽  
Automotive Industry ◽  
Peritectic Reaction ◽  
Composition Range ◽  
High Strength Steels ◽  
High Strength ◽  
Current Understanding ◽  
Motor Vehicles ◽  
Advanced High Strength Steels

The automotive industry is increasingly utilizing advanced high-strength steels, primarily to reduce the mass of motor vehicles. However, many of these steels fall within the peritectic composition range, which are notoriously difficult to cast by continuous casting techniques. Against this background, a brief review is given of our current understanding of the peritectic reaction as such and the subsequent peritectic phase transformations.

Niobium Containing Advanced High Strength Steels for Automotive Applications – Processing, Microstructure, and Properties

2013 ◽  
Vol 773-774 ◽  
pp. 325-335 ◽  
Author(s):  
Debanshu Bhattacharya
Keyword(s):  
Automotive Industry ◽  
Fuel Efficiency ◽  
High Strength Steels ◽  
High Strength ◽  
Dual Phase ◽  
Trip Steels ◽  
Advanced High Strength Steels ◽  
Energy Absorbing ◽  
Bake Hardenability ◽  
Very High

Two major drivers for the use of advanced steels in the automotive industry are fuel efficiency and increased safety performance. Fuel efficiency is mainly a function of weight of steel parts, which in turn, is controlled by gauge and design. Safety is determined by the energy absorbing capacity of the steel used to make the part. All of these factors are incentives for the automobile manufacturers to use Advanced High Strength Steels (AHSS) to replace the conventional steels used to manufacture automotive parts in the past. AHSS is a general term used to describe various families of steels. The most common AHSS is the dual-phase steel that consists of a ferrite-martensite microstructure. These steels are characterized by high strength, good ductility, low tensile to yield strength ratio and high bake-hardenability. Another class of AHSS is the complex-phase or multi-phase steel which has a complex microstructure consisting of various phase constituents and a high yield to tensile strength ratio. Transformation Induced Plasticity (TRIP) steels is another class of AHSS steels finding interest among the U.S. automakers. These steels consist of a ferrite-bainite microstructure with significant amount of retained austenite phase and show the highest combination of strength and elongation, so far, among the AHSS in use. High level of energy absorbing capacity combined with a sustained level of high n value up to the limit of uniform elongation as well as high bake hardenability make these steels particularly attractive for safety critical parts and parts needing complex forming. A relatively new class of AHSS is the Quenching and Partitioning (Q&P) steels. These steels seem to offer higher ductility than the dual-phase steels of similar strengths or similar ductility as the TRIP steels at higher strengths. Finally, martensitic steels with very high strengths are also in use for certain parts. The most recent initiative in the area of AHSS is the so-called 3rd Generation AHSS. These steels are designed to fill the region between the dual-phase/TRIP and the Twin Induced Plasticity (TWIP) steels with very high ductility at strength levels comparable to the conventional AHSS. Enhanced Q&P steels may be one method to achieve this target. Other ideas include TRIP assisted dual phase steels, high manganese steels and higher carbon TRIP type steels. In this paper, some of the above families of advanced high strength steels for the automotive industry will be discussed with particular emphasis on the role of niobium.

scholarly journals Adhesive Wear Resistance of Low Temperature Austempered and Quenched and Partitioned Niobium Alloyed Steels

2019 ◽  
Author(s):  
Pedro Gabriel Bonella de Oliveira ◽  
Ricardo Tadeu Junior Aureliano ◽  
Luiz Carlos Casteletti ◽  
André Itman Filho ◽  
Amadeu Lombardi Neto ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Low Temperature ◽  
Automotive Industry ◽  
Adhesive Wear ◽  
High Strength Steels ◽  
High Strength ◽  
Wear Performance ◽  
Advanced High Strength Steels ◽  
Safety Improvement ◽  
Present Complex

Abstract The quest for safety improvement with weight reduction of vehicles and consequently lower fuel consumption, led the automotive industry to begin research into the third generation of advanced high strength steels. These steels present complex microstructures, composed of martensite, bainite and stable retained austenite. Two of the main treatments for obtaining these microstructures are the low temperature austempering and Quenching and Partitioning (Q&P). The objective of this work is to evaluate the microhardness and adhesive wear performance of a high silicon steel alloyed with niobium submitted to the treatments mentioned above. The austempering treatment was conducted at 340 °C for 1 and 3 hours. Partitioning steps in Q&P were performed at 250 °C for 10, 30 and 60 minutes. Results shows that niobium addition promotes changes in the bainite morphology which improved the wear resistance.

scholarly journals Development of Advanced High Strength Automotive Steels

2021 ◽  
Vol 4 (1) ◽  
pp. 9-17
Author(s):  
Miklós Tisza
Keyword(s):  
Automotive Industry ◽  
First Generation ◽  
Driving Forces ◽  
Raw Materials ◽  
High Strength Steels ◽  
High Strength ◽  
Point Of View ◽  
Raw Material ◽  
Advanced High Strength Steels ◽  
Harmful Emissions

Abstract In recent decades, the automotive industry has faced ever-increasing demands. Increasing requirements can be observed in terms of both consumer expectations and legal requirements. On the consumer side, there is a demand for cars that are as economical as possible with lower fuel consumption, but providing also greater comfort and safety. These requirements are accompanied, from a legal point of view by more rigorous environmental regulations and requirements concerning the reduction of harmful emissions. Meeting these often-contradictory requirements is a growing challenge for car manufacturers and raw material suppliers, as well. Meeting the requirements in the most versatile way has resulted in tremendous progress over the last 40–50 years, both in the automotive industry and in the production and development of raw materials. The first part of this series of papers summarizes the main requirements in the automotive industry, as the main driving forces for material developments. Furthermore, the main types and properties of traditional high-strength steels, as well as the so-called first-generation Advanced High-Strength Steels will be introduced. In the second part, the main types and manufacturing processes of second generation advanced high-strength steels will be analyzed and some of the current steel developments will be presented through the results of the three generations of Advanced High-Strength Steels.

scholarly journals The Evaluation of Laser Weldability of the Third-Generation Advanced High Strength Steel

Metals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1051 ◽  
Author(s):  
António B. Pereira ◽  
Rafael O. Santos ◽  
Bruno S. Carvalho ◽  
Marilena C. Butuc ◽  
Gabriela Vincze ◽  
...  
Keyword(s):  
Automotive Industry ◽  
Greenhouse Gas Emission ◽  
High Strength Steels ◽  
High Strength ◽  
Tensile Tests ◽  
Weld Bead ◽  
Uniaxial Tensile ◽  
Third Generation ◽  
Advanced High Strength Steels

To meet the demands of vehicular safety and greenhouse gas emission reduction, the automotive industry is increasingly using advanced high strength steels (AHSS) in the production of the components. With the development of the new generation of AHSS, it is essential to study their behavior towards manufacturing processes used in the automotive industry. For this purpose, the welding capability of newly developed third-generation Gen3 980T steel was investigated using the Nd:YAG (Neodymium:Yittrium Aluminum Garnet) laser-welding with different parameter conditions. The analysis was made by uniaxial tensile tests, micro-hardness, Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). The criteria used to evaluate the quality of the weld were the distance between the fracture and the weld bead and the surface finish. A relationship between the quality of the weld and the energy density was observed, expressed by a partial penetration for values below the optimal, and by irregularities in the weld bead and a high number of spatters for the values above the optimal.

Advanced High Strength Steels: New Requirements of the Automotive Industry

2010 ◽  
Author(s):  
Carlos Alberto Silva de Miranda ◽  
Wagner Duarte Flores ◽  
Mariana de Melo Silva
Keyword(s):  
Automotive Industry ◽  
High Strength Steels ◽  
High Strength ◽  
Advanced High Strength Steels

The Mechanical Properties and Structure Evolution for High-Manganese TWIP Steel Wires

2013 ◽  
Vol 199 ◽  
pp. 524-527
Author(s):  
Zbigniew Muskalski ◽  
Sylwia Wiewiórowska ◽  
Marcin Pełka
Keyword(s):  
Mechanical Properties ◽  
Automotive Industry ◽  
High Strength Steels ◽  
High Strength ◽  
Structure Evolution ◽  
Advanced High Strength Steels ◽  
Steel Wires ◽  
Heat Treated ◽  
Increasing Demand ◽  
Multiphase Steels

The increasing demand by the automotive industry has resulted in a search for materials of increasingly high mechanical properties and, at the same time, plastic deformability. These requirements are met by AHSS (Advanced High-Strength Steels) multiphase steels. The group of AHSS type steels may include: diphase (DP), TRIP-effect, hot formed (HF) martensitic, plastic formed heat treated (PFHT), and TWIP-effect steels.

scholarly journals Advanced high strength steels for automotive industry

2012 ◽  
Vol 48 (2) ◽  
pp. 118-131 ◽  
Author(s):  
J. Galán ◽  
L. Samek ◽  
P. Verleysen ◽  
K. Verbeken ◽  
Y. Houbaert
Keyword(s):  
Automotive Industry ◽  
High Strength Steels ◽  
High Strength ◽  
Advanced High Strength Steels

scholarly journals Investigation into the dephosphorization of ferromanganese alloys for the production of advanced high-strength steel

2021 ◽  
Vol 121 (9) ◽  
pp. 1-9
Author(s):  
M.P. Maphutha ◽  
J.D. Steenkamp ◽  
P.C. Pistorius
Keyword(s):  
Partition Coefficient ◽  
Steel Industry ◽  
High Strength Steel ◽  
Induction Furnace ◽  
High Strength Steels ◽  
High Strength ◽  
Laboratory Scale ◽  
Motor Vehicles ◽  
Advanced High Strength Steel ◽  
Advanced High Strength Steels

Advanced high-strength steels (AHSS) are sophisticated materials being developed by the steel industry to mitigate challenges related to the performance of motor vehicles. To meet the requirements of AHSS, the ferromanganese alloys (FeMn) utilized in the production of the steel are required to contain acceptable levels of unwanted impurities, i.e. P, S, N, H, and C. The focus of the current study was to investigate dephosphorization of ferromanganese to produce a low-P alloy that could be effectively utilized in the production of AHSS. The study involved conducting laboratory-scale testwork to study the efficiency of CaO-based slag systems to dephosphorize FeMn alloys. The addition of Na2O, CaF2, and BaO to MnO-CaO-SiO2 slag was considered. The test work was carried out in a 25 kW induction furnace at temperatures of 1350°C, 1400°C, and 1450°C. The P partition coefficient (Lp) remained small at <1, which is an indication that dephosphorization had not been achieved. The baseline slag, comprising 40%CaO-40%SiO2-20%MnO, reported higher Lpvalues. Addition of Na2O and CaF2 did not show any further benefit. Substituting half of the CaO by BaO, resulted in similar Lpvalues to those of the baseline slag under conditions of 1350°C and 1450°C at 30 minutes. In summary, based on the Lpvalues obtained, the conditions investigated with the CaO-based slags appeared to have been unfavourable for dephosphorization of FeMn alloys, as most of this impurity element remained in the alloy.

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