天津大强钢铁有限公司

天津大强钢铁有限公司成立于1992年，占地面积15万平方米，注册资金4800万元，现有资产近两亿元，其中固定资产9000万，职工550人。公司以自我积累、求实创新为经营理念，现已发展成为一个生产弹簧扁钢、带钢、犁铧钢、低氧铜盘条和低松弛预应力钢绞线等多个产品的大型企业。

Strength and Toughness of Steel Fibre Reinforced Reactive Powder Concrete Under Blast Loading

The blast resistance of structures used in buildings needs to be investigated due to the increased threat of a terrorist attack. The damage done by Composition B or Powergel to steel fibre reinforced reactive powder concrete （SFRPC） panels and ordinary reinforced concrete （RC） panels of equivalent static flexural strength is compared. A 0. 5 kg charge was detonated at a distance of 0. 1 m from the 1. 3 m × 1. 0 m × 0. 1 m （thick） panels, which were simply supported and spaning 1.3 m. Dynamic displacement measurements, high-speed video recording and visual examination of the panels for spall and breach were undertaken. The SFRPC panels withstood the bare charge blast better than the reinforced ordinary concrete panels. Neither type of panel was breached using a O. 5 kg charge, The RC panel exhibited more spalling when Composition B was used. Under successive Composition B loading conditions, the RC panel was breached. In comparison the SFRPC panel was not breached. Exposure to fragmenting charge loading conditions confirmed these performance differences between the SFRPC panel and the reinforced ordinary concrete panel.

Mechanical Behavior of a Glass-fiber Reinforced Composite to Steel Joint for Ships

The use of a glass-fiber reinforced composite in marine structures is becoming more common, particularly due to the potential weight savings. The mechanical response of the joint between a glass-fiber reinforced polymer （GRP） superstructure and a steel hull formed is examined and subsequently modified to improve performance through a combined program of modeling and testing. A finite-element model is developed to predict the response of the joint. The model takes into account the contact at the interface between different materials, progressive damage, large deformation theory, and a non-linear stress-strain relationship. To predict the progressive failure, the analysis combines Hashin failure criteria and maximum stress failure criteria. The results show stress response has a great influence on the strength and bearing of the joint. The Balsawood-steel interface is proved to be critical to the mechanical behavior of the joint. Good agreement between experimental results and numerical predictions is observed.

Effect of fiber angle on LYP steel shear walls behavior

Steel shear wall(SSW) was properly determined using numerical and experimental approaches.The properties of SSW and LYP(low yield point) steel shear wall(LSSW) were measured.It is revealed that LSSW exhibits higher properties compared to SSW in both elastic and inelastic zones.It is also concluded that the addition of CFRP(carbon fiber reinforced polymers) enhances the seismic parameters of LSSW(stiffness,energy absorption,shear capacity,over strength values).Also,stress values applied to boundary frames are lower due to post buckling forces.The effect of fiber angle was also studied and presented as a mathematical equation.

Forced transverse vibration of rolls for four-high rolling mill

In order to investigate the forced transverse vibration of rolls under distributed draught pressure and moment of bending roll force, the forced transverse vibration model of rolls for four-high rolling mill was established. The work roll and backup roll were considered as elastic continuous bodies that were joined by a Winkler elastic layer. According to Euler-Bemoulli beam theory, the forced transverse vibration of rolls was analyzed based on modal superposition method. The forced vibration equations were established when the draught pressure and moment of bending roll force were imposed on the rolls respectively. Numerical modeling was made on 2 030 mm cold tandem rolling mill of Baoshan Iron and Steel Company. Simulation results show that when the work roll is only subjected to different forms of draught pressures, the vibration curves of work roll and backup roll are quadratic curves with amplitudes of 0.3 mm and 45 μm, respectively. When only the moments of bending roll force are imposed on the work roll and backup roll, the vibration curves of work roll and backup roll are quadratic curves, and the amplitudes are 5.0 and 1.6 μm, respectively. The influence of moment of bending roll force on the vibration of work roll is related with the bending roll force.

An ultrahigh strength steel produced through deformation-induced ferrite transformation and Q&P process

In this work,DIFT technology and Q&P process were combined in order to introduce ultrafine-grained ferrite into the matrix of martensite and retained austenite to develop a new kind of advanced high strength steel,and two kinds of steels were investigated by this novel combined process.The newly designed process resulted in a sophisticated microstructure of a large amount of ferrite(about 5 m in diameter),martensite and a considerable amount of retained austenite for TRIP 780 steel.The ultimate tensile strength can reach about 1200 MPa with elongation above 16% for TRIP 780,that is much higher than the one solely treated by Q&P process.Tensile tests showed that both steels with the novel combined process achieved a good combination of strength and ductility,indicating that the new process is promising for the new generation of advanced high strength steels.

Large magnetocaloric effect in metamagnetic HoPdAl

Magnetic properties and magnetocaloric effects （MCEs） of the HoPdA1 compounds with the hexagonal ZrNiAl-type and the orthorhombic TiNiSi-type structures are investigated. Both the compounds are found to be antiferromagnet with the Nrel tem- perature TN=12 and 10 K, respectively. A field-induced metamagnetic transition from antiferromagnetic （AFM） state to ferro- magnetic （FM） state is observed below TN. For the hexagonal HoPdA1, a small magnetic field can induce an FM-like state due to a weak AFM coupling, which leads to a high saturation magnetization and gives rise to a large MCE around TN. The maxi- mal value of magnetic entropy change （ASM） is -20.6 J/kg K with a refrigerant capacity （RC） value of 386 J/kg for a field change of 0-5 T. For the orthorhombic HoPdA1, the critical field required for metamagnetic transition is estimated to be about 1.5 T, showing a strong AFM coupling. However, the maximal ASM value is still -13.7 J/kg K around TN for a field change of 0-5 T. The large reversible ASM and considerable RC suggest that HoPdA1 may be an appropriate candidate for magnetic re- frigerant in a low temperature range.