Establishment of Processing Maps for 25vol.% B4CP/AA6061 Composite and its Application in Hot Pack-Rolling Process

The hot workability and hot pack-rolling process of B4CP/AA6061 composite were studied. The results showed that the addition of B4C particles could effectively promote the dynamic recrystallization (DRX) process of the composite. DRX and DRX grains growth were dominant deformation mechanism during hot deformation of B4CP/AA6061composite. Typical instability defects included micro voids and particle aggregation. The optimum processing parameters for good workability were obtained in the temperature range of 450°C-500°C and strain rate range of 0.01s-1-0.1s-1. According to the flow stress curves and processing maps, a temperature of 500°C and a rolling velocity of 40 mm/s were chosen for pack-rolling experiments. The pack-rolled composite sheets in the RD and TD showed more homogeneous DRX grains than as-HIPed microstructures, which might indicate that hot pack-rolling could lead to more homogeneous microstructures without any edge cracking and surface cracking.

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Hot Deformation Behavior Considering Strain Effects and Recrystallization Mechanism of an Al-Zn-Mg-Cu Alloy

Materials ◽

10.3390/ma13071743 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1743 ◽

Cited By ~ 3

Author(s):

Lei Luo ◽

Zhiyi Liu ◽

Song Bai ◽

Juangang Zhao ◽

Diping Zeng ◽

...

Keyword(s):

Dynamic Recrystallization ◽

Hot Deformation ◽

Deformation Behavior ◽

Processing Parameters ◽

Strain Rate Range ◽

Hot Compression ◽

Processing Maps ◽

Hot Deformation Behavior ◽

Recrystallization Mechanism ◽

Cu Alloy

The hot deformation behavior of an Al-Zn-Mg-Cu alloy was investigated by hot compression test at deformation temperatures varying from 320 to 440 °C with strain rates ranging from 0.01 to 10 s−1. The results show that the Mg(Zn, Cu)2 particles as a result of the sufficient static precipitation prior to hot compression have an influence on flow softening. A constitutive model compensated with strain was developed from the experimental results, and it proved to be accurate for predicting the hot deformation behavior. Processing maps at various strains were established. The microstructural evolution demonstrates that the dominant dynamic softening mechanism stems from dynamic recovery (DRV) and partial dynamic recrystallization (DRX). The recrystallization mechanism is continuous dynamic recrystallization (CDRX). The microstructure observations are in good agreement with the results of processing maps. On account of the processing map and microstructural observation, the optimal hot processing parameters at a strain of 0.6 are at deformation temperature range of 390–440 °C and strain rate range of 0.010–0.316 s−1 with a peak efficiency of 0.390.

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Effect of Strain Rate on Hot Ductility of a Duplex Stainless Steel

Advances in Materials Science and Engineering ◽

10.1155/2019/6810326 ◽

2019 ◽

Vol 2019 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Zhenhua Wang ◽

Wenyuan Ma ◽

Chengming Wang

Keyword(s):

Strain Rate ◽

Hot Forging ◽

Total Elongation ◽

Strain Rate Range ◽

Hot Ductility ◽

Hot Workability ◽

Crack Tips ◽

The Difference ◽

Edge Cracking ◽

Reduction In Area

Duplex stainless steels (DSSs) often have bad hot workability. In this study, specimens of 2205 DSS were hot tensioned over a strain rate range from 0.005 s–1 to 50 s–1 to examine the hot ductility. The crack morphology was observed, and the dependence of hot ductility on the strain rate was analyzed. From 0.005 s–1 to 0.5 s–1, both the total elongation and the reduction in area increased with the strain rate. The reduction in area exhibited a small decrease when the strain rate was greater than 0.5 s–1. More than 85% of cracks formed between the ferrite and austenite, and no less than 70% of crack tips propagated between the ferrite and austenite. When the strain rate was increased from 0.005 s–1 to 0.5 s–1, dynamic recrystallization was promoted in the austenite, and the number fraction of low-angle grain boundaries in the ferrite was improved. The higher strain rate reduced the difference between ferrite and austenite in hardness, which improved the hot ductility. For 2205 DDS, the suggested strain rate is 0.5 s–1 and above to avoid surface and edge cracking during hot forging or hot rolling. The findings will be of value for the understanding of hot ductility of DSSs and other dual-phase alloys.

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Effects of hot-pack rolling process on microstructure, high-temperature tensile properties, and deformation mechanisms in hot-pack rolled thin Ti–44Al–5Nb-(Mo, V, B) sheets

Materials Science and Engineering A ◽

10.1016/j.msea.2019.138197 ◽

2019 ◽

Vol 764 ◽

pp. 138197 ◽

Cited By ~ 3

Author(s):

T.R. Li ◽

G.H. Liu ◽

M. Xu ◽

B.X. Wang ◽

H.Z. Niu ◽

...

Keyword(s):

High Temperature ◽

Tensile Properties ◽

Rolling Process ◽

Deformation Mechanisms ◽

Pack Rolling ◽

High Temperature Tensile ◽

High Temperature Tensile Properties ◽

Hot Pack

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Experience of Hot Pack Rolling Application for Production of Specific Steels or Creep Resistant Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.989.699 ◽

2020 ◽

Vol 989 ◽

pp. 699-704

Author(s):

Nikita S. Deryabin ◽

Sergey M. Chernyshev ◽

Sergey N. Veselkov

Keyword(s):

Hot Rolling ◽

Deformation Behavior ◽

Import Substitution ◽

Rolling Process ◽

Plastic Range ◽

Pack Rolling ◽

Hot Rolling Process ◽

Hot Rolled ◽

Rolled Plates ◽

Hot Pack

Under the current conditions, the consumption of special purpose alloys or steels is growing. This is due to the development of the import substitution program. It should be noted, that such materials possess specific deformation behavior, which requires providing particular conditions of a hot rolling process. One of the characteristics of the deformation behavior is the narrow thermal plastic range. Therefore, it is necessary to conduct a hot rolling in several stages, which include interchange of heating and rolling processes. For the purpose to resolve the issue, the experience of the multilayer hot rolling of plates has been investigated where all advantages of this way of a hot rolling process were used. Based on the method of the multilayer hot rolling, the pack rolling has been developed which gives the possibility of production of hot-rolled plates from special purpose alloys or steels.

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The Effects of Hot-Pack Coating Materials on the Pack Rolling Process and Microstructural Characteristics during Ti-46Al-8Nb Sheet Fabrication

Materials ◽

10.3390/ma13030762 ◽

2020 ◽

Vol 13 (3) ◽

pp. 762

Author(s):

Huang ◽

Liao ◽

Yu ◽

Liu ◽

Wang

Keyword(s):

Stainless Steel ◽

Titanium Alloy ◽

Grain Boundary ◽

Rolling Process ◽

Interfacial Reactions ◽

Stress Strain ◽

Microstructural Characteristics ◽

Local Flow ◽

Pack Rolling ◽

Hot Pack

The effects of the package materials on the hot workability and stress-strain characteristics of high-Nb TiAl alloy with a nominal composition of Ti-46Al-8Nb (in at.%) were systematically studied via “sandwich structure” hot compression. TiAl sheet fabrication was conducted by hot pack rolling, and the microstructural characteristics and deformation mechanisms were investigated. Based on the analysis of compressed samples and stress-strain curves, the stainless steel/TiAl structure showed better deformation compatibility with homogeneous deformation and decreasing resistance. However, severe interfacial reactions were inevitable. Meanwhile, for the titanium alloy/TiAl structure, few interfacial reactions happened, but wavy deformation and high resistance complicated the compression process. Finally, a package structure with an outer stainless steel isolation layer and inner titanium alloy was determined for the pack rolling process. A TiAl sheet with no crack defects was obtained with 80% reduction. The pack-rolled TiAl sheet took on alternate microstructure of the grain-boundary Al-enriched ribbons and elongated lamellar colonies ribbons. The grain-boundary recrystallized α2 phase, lumpy γ phase, and massive α2/γ lamellae could be observed, which led to the scatter microstructure. The microstructural characteristics mainly resulted from the solute segregations of as-cast Ti-46Al-8Nb alloys, which triggered the local flow softening and deformation incompatibility during hot pack rolling.

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Identification of Stable Processing Parameters in Ti–6Al–4V Alloy from a Wide Temperature Range Across β Transus and a Large Strain Rate Range

High Temperature Materials and Processes ◽

10.1515/htmp-2014-0129 ◽

2015 ◽

Vol 0 (0) ◽

Cited By ~ 1

Author(s):

Guo-Zheng Quan ◽

Hai-Rong Wen ◽

Shi-Ao Pu ◽

Zhen-Yu Zou ◽

Dong-Sen Wu

Keyword(s):

Large Strain ◽

Processing Parameters ◽

Strain Rate Range ◽

Strain Rates ◽

Hot Workability ◽

Rate Range ◽

Measured Stress ◽

Strain Data ◽

Large Strain Rate ◽

Stable Processing

AbstractThe hot workability of Ti–6Al–4V alloy was investigated according to the measured stress–strain data and their derived forms from a series of hot compressions at the temperatures of 1,023–1,323 K and strain rates of 0.01–10 s

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ATI 425

Alloy Digest ◽

10.31399/asm.ad.ti0133 ◽

2004 ◽

Vol 53 (7) ◽

Keyword(s):

Fracture Toughness ◽

Chemical Process ◽

Aerospace Industry ◽

Processing Parameters ◽

Process Industry ◽

Hot Workability ◽

Chemical Process Industry ◽

Armor Plate ◽

Ballistic Protection ◽

Hot Rolled

Abstract ATI 425 was originally developed for hot-rolled armor plate to provide ballistic protection comparable to Ti-6Al-4V and has been evaluated against a variety of projectile threats for use as armor. While processing the alloy for armor plate applications, it was observed that the material exhibited very good hot workability, permitting a more lenient window of processing parameters than necessary for Ti-6Al-4V. Versatility then expanded, and applications now exist in the chemical process industry (CPI) and in the aerospace industry. This datasheet provides information on composition, physical properties, and tensile properties as well as fracture toughness and fatigue. It also includes information on corrosion resistance. Filing Code: TI-133. Producer or source: ATI Wah Chang, Allegheny Technologies. Originally published March 2004, revised July 2004.

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