• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.172-177
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• 2021

The microstructure and texture of three 316L foils of 25 ㎛ thickness, which were subjected to different manufacturing process, were systematically characterized using advance analytical techniques. Then, the electrochemical property of the 316L foils in simulated pressurized water reactor (PWR) solution was analyzed using potentiodynamic polarization. The results showed that final rolling strain and annealing temperature had evident effect on grain size, fraction of recrystallization, grain boundary type and texture distribution. It was suggested that large final rolling strain could transfer Brass texture to Copper texture; low annealing temperature could limit the formation of preferable orientations in the rolling process to reduce anisotropy. Potentiodynamic polarization test showed that all samples exhibited good corrosion performance in the simulated primary PWR solution.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.262.1-262
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• 2002

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.92-95
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• 2003

Asymmetric rolling of AA1050 Al alloy sheets was performed to obtain the shear textures for improving the deep drawability and the grain refinement. The effect of roll velocity ratio on the texture and the grain refinement of 50％ asymmetrically rolled sheets was studied. The textures of the asymmetrically rolled sheets after annealing at 400$^{\circ}C$ for 1 h was also investigated.

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.73-73
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• 2003

• Korean Journal of Materials Research
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• v.33 no.11
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• pp.439-446
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• 2023

Changes in the microstructure and mechanical properties of as-roll-bonded AA6061/AA5052/AA1050 three-layered sheet with increasing annealing temperature were investigated in detail. The commercial AA6061, AA5052 and AA1050 sheets with 2 mm thickness were roll-bonded by multi-pass rolling at ambient temperature. The roll-bonded Al sheets were then annealed for 1 h at various temperatures from 200 to 400 ℃. The specimens annealed up to 250 ℃ showed a typical deformation structure where the grains are elongated in the rolling direction in all regions. However, after annealing at 300 ℃, while AA6061 and AA1050 regions still retained the deformation structure, but AA5052 region changed into complete recrystallization. For all the annealed materials, the fraction of high angle grain boundaries was lower than that of low angle grain boundaries. In addition, while the rolling texture of the {110}<112> and {123}<634> components strongly developed in the AA6061 and AA1050 regions, in the AA5052 region the recrystallization texture of the {100}<001> component developed. After annealing at 350 ℃ the recrystallization texture developed in all regions. The as-rolled material exhibited a relatively high tensile strength of 282 MPa and elongation of 18 %. However, the tensile strength decreased and the elongation increased gradually with the increase in annealing temperature. The changes in mechanical properties with increasing annealing temperature were compared with those of other three-layered Al sheets fabricated in previous studies.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.55-58
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• 2003

We fabricated the textured Ni substrate and evaluated the effects of processing variables on microstructural evolution and texture transformation. Ni-rods as an initial specimen were prepared by two different methods, i.e., powder metallurgy(P/M) and plasma arc melting(PAM) The texture of the substrate was characterized by pole-figure and surface condition was evaluated by atomic force microscopy. It was observed that the texture of substrate made by P/M did not significantly varied with annealing temperature of 800~120$0^{\circ}C$ and the full-width at half-maximums (FWHM) of both in-plane and out-of-plane were 9$^{\circ}$~10$^{\circ}$. On the other hand, the texture of substrate made by PAM was more dependent on the annealing temperature and the FWHMs of in-plane texture was 9$^{\circ}$~13$^{\circ}$ at the temperature range. In addition, twin texture, (221)＜221＞, was formed as the temperature increased further. The grain size of substrate made by P/M was smaller than that made by PAM and this difference was correlated to the microstructure of initial specimens.

• Korean Journal of Metals and Materials
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• v.47 no.1
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• pp.1-6
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• 2009

Magnesium alloys are drawing a lot of attention and have been extensively studied. The major obstacle to the practical application of the alloys is the poor formability at room temperature, originating basically from the insufficient number of slip system. Development of a proper texture is one promising solution to improve the formability. In the present work, after extrusion and full annealing, microstructures, texture developments and tensile properties of AZ31 Mg alloys are studied. After full annealing strong <1010>||ED fiber texture and weak <1120>+<1230>||ED fiber texture (c-axes in the radial direction) were developed. The textures are distinctly influencing the tensile properties, which can be understood in terms of the activation of basal slip modes. With the random orientation, which is developed in the $45^{\circ}$ sample to the extrusion direction, the better workability can be achieved at room temperature.

• Journal of the Korean Society for Heat Treatment
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• v.28 no.4
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• pp.171-180
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• 2015

The variation in microstructure and texture during continuous annealing was examined in a series of 1.6% Mn-0.1% Cr-0.3% Mo-0.005% B steels with carbon contents in the range of 0.010 to 0.030%. It was found that microstructure of hot band consisted of ferrite and pearlite as a consequence of high coiling temperature, and eutectoid carbon content was between 0.011% and 0.016%. Martensite ranged in volume fraction from 1.5% to 4.0% when annealed at $820{\circ}C$ according to the typical continuous annealing cycle. The critical martensite content for the continuous yielding was about 4% from stress-strain curves. The continuous yielding was obtained in the 0.030% carbon steel and 0.010% to 0.020% carbon steels revealed some yield point elongation ranging from 0.8% to 2.2% in as-annealed conditions. Higher tensile strength in the higher carbon steel is due to both increase in the martensite volume fraction and ferrite grain refinement. Decreasing the carbon content to 0.01% strengthened the intensities of ${\gamma}$-fiber textures, resulting in the increase in the $r_m$ value, which was caused by the lower volume fraction of martensite. The higher carbon steels showed the lower $r_m$ value of about 1.0.

• Korean Journal of Materials Research
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• v.4 no.1
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• pp.44-54
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• 1994

Effects of cooling rate, cold reduction %, continuous annealing treatments on the recrystallization texture structure of the A1 killed extra low carbon steel sheet contaning Ti, Nb, and B were investigated. The texture coefficient ratio TC (222)/TC (200) tends to increase with decreasing the cooling rate of the coling process and increasing cold reduction %. However, the texture coefficient ratio tends to decrease as the cold reduction % increases from 80% to 90%, which may be due to the change of the primary texture structure from {554} (225) to {ill] (1 1%). The optimum fabrication procedures for the steel sheet with a maximum texture coefficient ratio may be : furnance cooling after the coiling treatment, 80% cold reduction and the continuous annealing treatment of holding at 80O0C for 1 min., water quenching and then holding at $450^{\circ}C$ for 5min.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.136-137
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• 2003

Recrystallization textures of ferritic stainless steel sheets of STS 430, the crystallographic texture was modified by means of cross rolling and subsequent annealing. The conventional normal rolling led to the formation of ｛334｝＜483＞ in the final recrystallization texture. Cross rolling in the present work was performed by a 45$^{\circ}$rotation of RD around ND. After recrystallization annealing the cross-rolled samples displayed stronger｛111｝//ND orientations. The cross rolled sample displayed a higher resistance against ridging.