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Showing 1 to 19 of 19 for “"AHSS"”.
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Edge fracture of AHSS sheets under out-of-plane loading followed by in-plane loading
… materials such as Advanced High Strength Steels (AHSS) and aluminum alloys. A premature edge cracking is observed in components with blanked/trimmed/pierced edges during the subsequent metal forming process. To understand the underlying physical mechanism and to establish a reliable CAE model, the …
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Testing and prediction of failure of AHSS sheets at Die Radius and Sidewall using novel fracture apparatus
A new apparatus was constructed to fit the Impact and Crashworthiness Lab's dual actuator custom-made loading frame that has force or position control. The strip is pre-bent into an elbow configuration and fastened by the vertical and horizontal grips. One end of the metal strip is subjected to a …
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Material substitution in electric vehicle manufacturing : comparing advanced high strength steel and aluminum
… is to substitute Advanced High Strength Steel (AHSS) or aluminum in place of traditional mild steel. Aluminum is a lighter weight than AHSS, leading to greater reduction of battery and motor costs. However, it is more expensive to manufacture the vehicle body using aluminum compared to AHSS. …
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Effect of microstructure on the fracture response of advanced high strength steels
… four 780 MPa strength, and four 980 MPa strength AHSS grades produced with varying processing conditions. The grades were an uncoated DP780, a high yield DP780, a galvanized DP780, a TRIP780, a galvannealed DP980, a galvanized DP980, an uncoated DP980, and a fine grained DP980. All AHSS grades …
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Edge Fracture Prediction Of Dual Phase Steels With Consideration Of Microstructures
… recent years, Advanced High Strength Steels (AHSS) have been used for the lightweight structural design and manufacturing in automotive industry. This class of sheet metals are prone to edge fracture during stamping production, and the fracture often occurs at much lower strain than that …
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Development of LTTW consumables for the enhancement of mechanical properties and residual stress management in thin steel welded joints
… panels using advanced high strength steels (AHSS) is typically limited by the weldments. Low transformation temperature welding (LTTW) consumables are characterized by low martensite start temperature and large fraction of martensite forming in the weld. It can efficiently reduce the tensile …
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Development of a punching technique for ductile fracture testing over a wide range of stress states and strain rates
Advanced High Strength Steels (AHSS) are becoming increasingly popular in automotive design because of possible weight savings due to the high strength. However, traditional methods are not capable of predicting fracture in AHSS, leading to expensive redesign due to poor prediction of stamping and …
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Effect of Processing Path on Microstructure and Mechanical Properties of a Low Carbon, Low Alloy Advanced High Strength Steel
… variants of advanced high strength steels (AHSS) have been developed with the latest focus on 3rd generation AHSS. In this work, microstructural evolution and mechanical properties of an automotive grade low carbon, low alloy steel under air-cooled, water-quenched, and tempered conditions …
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Understanding the Phase Transformations of a Medium Manganese Steel as a Function of Carbon Content
… third-generation advanced high strength steel (AHSS). Potential applications for these steels are centered around the automotive industry due to their combination of high tensile strength, high tensile ductility, and low alloying cost. Previous studies at VT have been primarily focused on the …
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Experimental characterization and modeling of the plastic behavior of a thirdgeneration advanced high strength steel sheet
… generation of the advanced highstrength steels (AHSS) has attracted the automotive industry attention owing to its good compromise between the formability and production cost. The current development stage of these steels so far has few products available on the market, as well as little research …
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Jet impingement boiling heat transfer at low coiling temperatures
The production of advanced high strength steels (AHSS) for use in the automotive and construction industries requires complex control of runout table (ROT) cooling. Advanced high strength steels require coiling at temperatures below 500 °C in order to produce a complex multi-phase microstructure. …
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PERITECTIC BEHAVIOR DETECTION AND PREDICTION IN Fe-C-Si-Mn-Al SYSTEM
… grades such as Advanced high strength steels (AHSS), transformation induced plasticity (TRIP) steels, abrasion-resistant steels, advanced armor plate steels, and many newly proposed steel grades that contain high levels of silicon, manganese, and aluminum.</p> <p>The shell growth non-uniformity …
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Ductile fracture and structural integrity of pipelines & risers
… of the fact that Advance High Strength Steels (AHSS), such as X100 and X120, can address those issues, but is not yet ready to introduce them, due to incomplete understanding of their material properties and structural behavior in the plastic and near failure range. Therefore, the current thesis …
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Ductile fracture at intermediate stress triaxialities : experimental investigations and micro-mechanical modeling
… fracture of an Advanced High Strength Steel (AHSS), covering development of new experimental procedures, material characterization and phenomenological as well as micro-mechanical modeling of the onset of fracture. Based on an extensive multi-axial experimental program, the anisotropic …
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Desarrollo experimental y modelado computacional multiescala de la curva límite de formabilidad : aplicación a un acero dual-phase de alta resistencia
… de los aceros avanzados de alta resistencia (AHSS) para reducir el peso de partes automotrices. Esto resulta en una fuerte necesidad de determinar la respuesta límite del material frente a solicitaciones típicas de operaciones de conformado y el estudio de los factores que la influencian. La …
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Hot ductility of TWIP steels
… Induced Plasticity) steel is very promising AHSS (Advanced High Strength Steel) grade owing to its superior toughness and ductility. Recently it has attracted the interest of the automotive and steelmaking industries, as the need for reducing weight to provide better fuel efficiency is of …
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ATOMISTIC SIMULATION AND FIRST PRINCIPLES CALCULATION OF INTERFACIAL ENERGETICS OF GALVANIZED ADVANCED HIGH STRENGTH STEELS
… generation (3G) advanced high strength steels (AHSSs) have drawn significant attention in recent years because applications of AHSSs will enable vehicle mass reduction with safety standards met, which can reduce the emissions of greenhouse gases of vehicles. However, the increased concentration …
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Effects of deformation modes on the susceptibility of delayed fracture of advanced high strength steels
… fracture in advanced high strength steels (AHSSs) were evaluated using four types of commercially-produced sheet steels (DP780, DP980, TRIP780 and TRIP980). Specimens were strained by either uniaxial tension or bending prior to hydrogen charging and their delayed fracture response was …
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Development Of High Strength High Toughness Third Generation Advanced High Strength Steels.
… generation advanced high strength steels (AHSS's) are emerging as very important engineering materials for structural applications. These steels have high specific strength and thus will contribute significantly to weight reduction in automotive and other structural component. In this …