Influence of continuous annealing soaking temperature on fish-scaling resistance of ultra-low carbon steel for porcelain enameling

2019 ◽  
Vol 116 (2) ◽  
pp. 205
Author(s):  
Zaiwang Liu ◽  
Yonglin Kang ◽  
Yiding Li
Keyword(s):  
Grain Size ◽  
Volume Fraction ◽  
Hydrogen Permeation ◽  
Phase Particle ◽  
Continuous Annealing ◽  
Second Phase ◽  
Low Carbon ◽  
Scaling Resistance ◽  
Ferrite Grain Size ◽  
Soaking Temperature

The relationship between fish-scaling resistance of ultra-low carbon (ULC) enamel steel and continuous annealing soaking temperature was rarely studied before. In this paper, the influence of continuous annealing soaking temperature on microstructure, precipitation behavior and fish-scaling resistance of ULC steel for porcelain enameling was investigated. The results obtained were as follows: for ULC enamel steel, with the continuous annealing soaking temperature increasing from 750 °C to 840 °C, the mean diameter of second phase particle increased from 41 nm to 52 nm, the corresponding volume fraction decreased from 5.8 × 10−3 m3/m3 to 2.9 × 10−3 m3/m3, and the ferrite grain size grew from 13.4 µm up to 17.3 µm, the hydrogen permeation value (TH value) decreased from 32 min/mm2 to 12 min/mm2. The grain boundary and precipitates are main hydrogen traps, as the ferrite grain size increased and the volume fraction of second phase particles decreased, the fish-scaling resistance of ULC enamel steel decreased.

Study on the Effect of Sm2O3 Particle on Crystal Grain Size and Inclusion of Low Carbon Steel

2012 ◽  
Vol 524-527 ◽  
pp. 2049-2055
Author(s):  
Jun Peng ◽  
Yang Bing Li ◽  
Jian Wang ◽  
Rui Hua Guo ◽  
Sheng Li An ◽  
...  
Keyword(s):  
Grain Size ◽  
Phase Particle ◽  
Low Carbon Steel ◽  
Second Phase ◽  
Low Carbon ◽  
Improve Performance ◽  
Steel Product ◽  
Rare Earth Alloy ◽  
Average Size ◽  
Level 2

The second phase particle in steel can refine crystal grain and improve performance of steel products. In the paper, how Sm2O3 particle affecting on inclusion and crystal grain size of steel product was studied by adding Sm2O3 particle into steel. The result shows the Sm2O3 particle will not agglomerate and the content of inclusion in steel will not increase when the particle size is lower than 1.47μm while the content of inclusion will increase obviously when the size is higher than 3.41μm. The Sm2O3 particle can combine with sulfide inclusion and deoxided product, which has the same function as adding rare earth alloy into steel partially. So the Sm2O3 particle can refine the size of crystal grain of cast structure. The degree of crystal grain was reduced from level 2 to level 4-4.5 and the average size of crystal grain was reduced from 180μm to 90-75μm. And it can also reduce the size of crystal grain of rolled structure. The degree was reduced from level 6.5 to level 11 and it will decrease with increasing of adding content of Sm2O3 particle. The best economic and technical norms can be got when the l size of Sm2O3 particle is 1.47μm and the adding content is 0.5% of the content of metal.

Effect of Chromium and Nickel Additions on the Transformation Characteristic and Ferrite Grain Size Refinement of Low Carbon Structural Steels Containing 0.13% C

2016 ◽  
Vol 860 ◽  
pp. 158-164
Author(s):  
Md Mohar Ali Bepari ◽  
Mohiuddin Ahmed
Keyword(s):  
Heat Treatment ◽  
Grain Size ◽  
Optical Microscopy ◽  
Chromium Carbide ◽  
Volume Fraction ◽  
Structural Steels ◽  
Low Carbon ◽  
Austenite Grain Size ◽  
Austenite Grain ◽  
Ferrite Grain Size

The effect of small addition of chromium and nickel alone or in combination on the transformation characteristic and ferrite grain size of low carbon (0.13%C) structural steels have been studied by cooling suitable steels at four different cooling rates ranging from 120°C/min to 3.6° C/min from temperatures giving a constant austenite grain size of 37 μm. Radio Frequency generator with control system was used for the heat treatment of the steel samples. Optical microscopy of the heat treated samples was carried out. Ferrite grain size was determined from the fictitious ferrite grain size measured by mean linear intercept method and the volume fraction of pearlite obtained by optical microscopy and point counting. It was found that although the heat treatment of the steels was started from a common austenite grain size, their subsequent ferrite grain size after cooling at the same cooling rate were not the same. Both chromium and nickel enhance the formation of Widmanstatten structure. But chromium is more effective than nickel in the formation of Widmanstatten structure. It was also found that the undissolved particles of chromium carbide (Cr2C) present during austenitizing have no role in determining the ferrite grain size. The precipitating particles of chromium carbide (Cr2C) are excellent ferrite grain size refiners. Nickel refines the ferrite grain size. In presence of nickel, Cr2C precipitates are less effective than Cr2C precipitates in absence of nickel in the refinement of ferrite grain size.

Research on Key Technology of Normal Grain Growth for Second Phase Particle Materials by Cellular Automata Simulation

2012 ◽  
Vol 510 ◽  
pp. 772-775
Author(s):  
Zong Lei Gu ◽  
Yu Liang Yin
Keyword(s):  
Grain Size ◽  
Cellular Automata ◽  
Grain Boundaries ◽  
Grain Growth ◽  
Volume Fraction ◽  
Phase Particle ◽  
Second Phase ◽  
Pinning Mechanism ◽  
Simulation Results ◽  
Single Size

Based on cellular automata, a model of simulating grain growth was established and the key technologies of simulation was studied which including second phase particle of single size, multi-size distribution and different shapes generation technologies. The simulation result can accurately reflect the influence law of the second phase particle grain growth and its pinning mechanism. Grain boundaries can therefore more easily break free from the particles than in purely two-dimensional systems, resulting in fewer grain boundaryparticle intersections and a larger final grain size. For a given volume fraction f and size of the particles r, the final grain size increases with film thickness. Moreover, it was found that particles located in the middle of the film are most efficient in pinning grain boundaries. The simulation results are compared with Zener type relations and previous simulation results.

Strengthening and Improving Yield Asymmetry of Magnesium Alloys by Second Phase Particle Refinement Under the Guidance of Integrated Computational Materials Engineering

2015 ◽  
Vol 137 (3) ◽  
Author(s):  
Dongsheng Li ◽  
Curt Lavender
Keyword(s):  
Grain Size ◽  
Grain Refinement ◽  
Magnesium Alloys ◽  
Volume Fraction ◽  
Phase Particle ◽  
Fuel Efficiency ◽  
Co2 Production ◽  
Precipitate Size ◽  
Second Phase ◽  
Precipitate Volume Fraction

Improving yield strength and asymmetry is critical to expand applications of magnesium alloys in industry for higher fuel efficiency and lower CO2 production. Grain refinement is an efficient method for strengthening low symmetry magnesium alloys, achievable by precipitate refinement. This study provides guidance on how precipitate engineering will improve mechanical properties through grain refinement. Precipitate refinement for improving yield strengths and asymmetry is simulated quantitatively by coupling a stochastic second phase grain refinement model and a modified polycrystalline crystal viscoplasticity φ-model. Using the stochastic second phase grain refinement model, grain size is quantitatively determined from the precipitate size and volume fraction. Yield strengths, yield asymmetry, and deformation behavior are calculated from the modified φ-model. If the precipitate shape and size remain constant, grain size decreases with increasing precipitate volume fraction. If the precipitate volume fraction is kept constant, grain size decreases with decreasing precipitate size during precipitate refinement. Yield strengths increase and asymmetry approves to one with decreasing grain size, contributed by increasing precipitate volume fraction or decreasing precipitate size.

scholarly journals A Dislocation-Based Theory for the Deformation Hardening Behavior of DP Steels: Impact of Martensite Content and Ferrite Grain Size

2010 ◽  
Vol 2010 ◽  
pp. 1-16 ◽  
Author(s):  
Yngve Bergström ◽  
Ylva Granbom ◽  
Dirk Sterkenburg
Keyword(s):  
Plastic Deformation ◽  
Grain Size ◽  
Deformation Process ◽  
Volume Fraction ◽  
High Energy ◽  
Martensite Content ◽  
Plastic Deformation Process ◽  
Deformation Hardening ◽  
Dp Steels ◽  
Ferrite Grain Size

A dislocation model, accurately describing the uniaxial plastic stress-strain behavior of dual phase (DP) steels, is proposed and the impact of martensite content and ferrite grain size in four commercially produced DP steels is analyzed. It is assumed that the plastic deformation process is localized to the ferrite. This is taken into account by introducing a nonhomogeneity parameter, f(ε), that specifies the volume fraction of ferrite taking active part in the plastic deformation process. It is found that the larger the martensite content the smaller the initial volume fraction of active ferrite which yields a higher initial deformation hardening rate. This explains the high energy absorbing capacity of DP steels with high volume fractions of martensite. Further, the effect of ferrite grain size strengthening in DP steels is important. The flow stress grain size sensitivity for DP steels is observed to be 7 times larger than that for single phase ferrite.

Effect of Tailoring Martensite Shape and Spatial Distribution on Tensile Deformation Characteristics of Dual Phase Steels

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
B. Ravi Kumar ◽  
Vishal Singh ◽  
Tarun Nanda ◽  
Manashi Adhikary ◽  
Nimai Halder ◽  
...  
Keyword(s):  
Grain Size ◽  
Spatial Distribution ◽  
Volume Fraction ◽  
Tensile Deformation ◽  
Void Formation ◽  
Martensite Phase ◽  
Continuous Annealing ◽  
Dual Phase ◽  
Deformation Characteristics ◽  
Dp Steels

The authors simulated the industrially used continuous annealing conditions to process dual phase (DP) steels by using a custom designed annealing simulator. Sixty-seven percentage of cold rolled steel sheets was subjected to different processing routes, including the conventional continuous annealing line (CAL), intercritical annealing (ICA), and thermal cycling (TC), to investigate the effect of change in volume fraction, shape, and spatial distribution of martensite on tensile deformation characteristics of DP steels. Annealing parameters were derived using commercial software, including thermo-calc, jmat-pro, and dictra. Through selection of appropriate process parameters, the authors found out possibilities of significantly altering the volume fraction, morphology, and grain size distribution of martensite phase. These constituent variations showed a strong influence on tensile properties of DP steels. It was observed that TC route modified the martensite morphology from the typical lath type to in-grain globular/oblong type and significantly reduced the martensite grain size. This route improved the strength–ductility combination from 590 MPa–33% (obtained through CAL route) to 660 MPa–30%. Finally, the underlying mechanisms of crack initiation/void formation, etc., in different DP microstructures were discussed.

Effect of Rare Earth (RE) La on Solid Solution of Second Phase Particle and Austenite Grain Growth in Steel Containing High Niobium

2011 ◽  
Vol 189-193 ◽  
pp. 2869-2874 ◽  
Author(s):  
Wen Zhong Song ◽  
Qi Fang ◽  
Hui Ping Ren ◽  
Zi Li Jin ◽  
Hui Chang
Keyword(s):  
Solid Solution ◽  
Growth Rate ◽  
Rare Earth ◽  
Grain Growth ◽  
Phase Particle ◽  
Solution Temperature ◽  
Second Phase ◽  
Austenite Grain ◽  
Austenite Grain Growth ◽  
Soaking Temperature

The solid solution of the second phase particle and austenite grain growth behavior of the high niobium-containing RE steel was studied by mathematical calculation and extraction replica technique. The purpose of the study was to investigate the effects of Rare Earth La on austenite grain growth and propose an empirical equation for predicting the austenite grain size of RE steel. Austenite grain grows in an exponential law with the increase of heating temperature, while approximately in a parabolic law with the increase of holding time. Results show that the RE steel has good anti-coarsening ability at elevated temperatures. When soaking temperature is lower than 1250°C , AGS and growth rate are small for high niobium steel, but soaking temperature is lower than 1220°C , AGS and growth rate are small for RE steel. RE La can promote solid solution of second-phase particles Nb(C, N), the solution temperature decrease 30°C than high niobium steel.

Effects of Pulsed Magnetic Field on the Microstructure and Mechanical Properties of Mg97Y2Zn1 Alloy

2014 ◽  
Vol 1004-1005 ◽  
pp. 123-126 ◽  
Author(s):  
Jian Yin ◽  
Xiu Jun Ma ◽  
Jun Ping Yao ◽  
Zhi Jian Zhou
Keyword(s):  
Magnetic Field ◽  
Mechanical Properties ◽  
Grain Size ◽  
Volume Fraction ◽  
Pulsed Magnetic Field ◽  
Second Phase ◽  
Microstructure And Mechanical Properties ◽  
Magnetic Field Treatment ◽  
Semi Solid ◽  
Strength And Plasticity

Effect of pulsed magnetic field treatment on the microstructure and mechanical properties of Mg97Y2Zn1 alloy has been investigated. When the pulsed magnetic field is applied on the alloy in semi-solid state, the α-Mg was modified from developed dendrite to fine rosette, resulting in a refined solidification microstructure with the grain size decreased from 4 mm to 0.5 mm. The volume fraction of the second phase ( X phase) increased by about 10 %. The yield strength, fracture strength and plasticity were improved by 21 MPa, 38 MPa and 2.4 %, respectively. The improvement of mechanical properties was attributed to the refined grain size and increased volume fraction of X phase.

Sign in / Sign up

Export Citation Format

Share Document