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Online since: March 2014
Authors: Dong Liu, Yan Hui Yang, Jian Guo Wang, Guo Jie Gao
(a) top surface
(b) bottom surface
(c) cross section
Fig. 5 The TC11 alloy blisk
Table 3 The process parameters of numerical simulation
Parameters
Values
Initial temperature /[°C]
980(workpiece);260(dies)
Transfer time /[s]
20
Dwell time /[s]
4
Friction coefficient
0.25
Coefficient of heat exchange between the workpiece and dies / W/[m2·K]
20000(strike); 2000(dwell)
Coefficient of heat exchange with enviorement/ W/[m2·K]
18
Number of heat
3
Number of blow in each heat
5
Energy grade in each heat
0.45,0.75,0.75,0.85, 0.9
The distribution of thermomechanical parameters within final forging was shown in Fig. 6.
As can be seen from the above Figures, the microstructures of each sampling point are similar: 40 to 50 percent of the equiaxed α phase, distributed on the tranformed β matrix, the average grain size of α phase is about 15μm.
Recrystallization and Grain Growth in Hot Rolling.
As can be seen from the above Figures, the microstructures of each sampling point are similar: 40 to 50 percent of the equiaxed α phase, distributed on the tranformed β matrix, the average grain size of α phase is about 15μm.
Recrystallization and Grain Growth in Hot Rolling.
Online since: October 2012
Authors: Xiang Sheng Chen
China is now leading in the world in AGF projects, both in the number and in the scale of freezing projects.
Frozen clay is some kind of unsaturated soil with moisture, grain, gas and ice, which are very important for correcting test data.
Table 1 Parameters for creep constitutive Equation (2) of artificial frozen clay Sample number and Depth, m Moisture % A0, °CK(MPa)-B h-C K B C Temperature range R2 PJ258 28.9 19.33 2.6 1.88 0.21 -5~-25°C 0.9958 CS309 21.0 8.30 1.9 1.58 0.31 -5~-15°C 0.9980 CS312 17.3 3.31 1.9 3.06 0.39 -5~-15°C 0.9977 CS357 13.8 5.28 2.1 3.06 0.29 -5~-15°C 0.9895 XQ226a 21.0 7.99 2.8 1.42 0.29 -5~-15°C 0.9902 XQ226b 30.0 12.94 2.0 2.58 0.37 -5~-20°C 0.9955 A time-space-dependent design method and the stability of ice wall It is a long-term topic for researchers and engineers to tackle the deep shaft by AGF in thick clay layer.
Artificial frozen clay is some kind of unsaturated soil with moisture, grain (solid particle), gas and ice, which should be kept in mind when tests are carried out.
Frozen clay is some kind of unsaturated soil with moisture, grain, gas and ice, which are very important for correcting test data.
Table 1 Parameters for creep constitutive Equation (2) of artificial frozen clay Sample number and Depth, m Moisture % A0, °CK(MPa)-B h-C K B C Temperature range R2 PJ258 28.9 19.33 2.6 1.88 0.21 -5~-25°C 0.9958 CS309 21.0 8.30 1.9 1.58 0.31 -5~-15°C 0.9980 CS312 17.3 3.31 1.9 3.06 0.39 -5~-15°C 0.9977 CS357 13.8 5.28 2.1 3.06 0.29 -5~-15°C 0.9895 XQ226a 21.0 7.99 2.8 1.42 0.29 -5~-15°C 0.9902 XQ226b 30.0 12.94 2.0 2.58 0.37 -5~-20°C 0.9955 A time-space-dependent design method and the stability of ice wall It is a long-term topic for researchers and engineers to tackle the deep shaft by AGF in thick clay layer.
Artificial frozen clay is some kind of unsaturated soil with moisture, grain (solid particle), gas and ice, which should be kept in mind when tests are carried out.
Online since: January 2016
Authors: Karel Dvořák, Dusan Dolak, Iveta Hájková
The advantages of this technology is reduction of reaction temperature of the material, increasing the reactivity of materials, shorter milling times (reduce energy demands) and reducing the number of technological steps.
On these micrographs we can see, that additional milling resulted in to considerable reduction in grain size.
The grains were cubicle shaped, evenly milled, without a higher content of coarse particles.
Acknowledgements This work was financially supported by project number: 15-08755S “Study of effects of samples preparation on inorganic binders final properties” and project No.
On these micrographs we can see, that additional milling resulted in to considerable reduction in grain size.
The grains were cubicle shaped, evenly milled, without a higher content of coarse particles.
Acknowledgements This work was financially supported by project number: 15-08755S “Study of effects of samples preparation on inorganic binders final properties” and project No.
Online since: January 2010
Authors: Mitsuo Niinomi, Kazuya Oribe, Toshikazu Akahori, Masaaki Nakai, Kengo Narita, Harumi Tsutsumi
Equiaxial grains with grain diameters in the range of 5-15 µm were observed in the TNTZ
rods by optical microscopy.
BF image SAD pattern BF image SAD pattern Mechanical Properties of T�TZ Rods The cyclic stress-fatigue life (the number of cycles to failure) curves, that is, S-N curves, obtained from the four-point bending fatigue tests of each TNTZ rod and the Ti64 rod are shown in Fig.3.
Moreover, the fatigue strength of the Ti64 rod exceeds the fatigue strengths of the every TNTZ rods in both low and high cycle fatigue regions. 0 200 400 600 800 1000 1200 1000 10000 100000 1000000 10000000 Number of Cycles to Failure, �f Fig. 3 S-N curves of TNTZ rods subjected to various heat treatments and Ti64 rod obtained from four-point bending fatigue tests.
BF image SAD pattern BF image SAD pattern Mechanical Properties of T�TZ Rods The cyclic stress-fatigue life (the number of cycles to failure) curves, that is, S-N curves, obtained from the four-point bending fatigue tests of each TNTZ rod and the Ti64 rod are shown in Fig.3.
Moreover, the fatigue strength of the Ti64 rod exceeds the fatigue strengths of the every TNTZ rods in both low and high cycle fatigue regions. 0 200 400 600 800 1000 1200 1000 10000 100000 1000000 10000000 Number of Cycles to Failure, �f Fig. 3 S-N curves of TNTZ rods subjected to various heat treatments and Ti64 rod obtained from four-point bending fatigue tests.
Online since: December 2016
Authors: Hua Liang Wan, Qi Zhi Wang, Hui Xing Lin
The columnar grains are observed.
From the studies in [8, 16], the number of lack-of-fusion porosity is much less than the number of gas porosity.
From the analysis in the section 2.1, the assumptions about the mechanical model are made: 1) The columnar grain of AM materials results in the different yield stress.
From the studies in [8, 16], the number of lack-of-fusion porosity is much less than the number of gas porosity.
From the analysis in the section 2.1, the assumptions about the mechanical model are made: 1) The columnar grain of AM materials results in the different yield stress.
Online since: August 2013
Authors: Jia Ju Wu, Yong Kang Xu, Zheng Jing Wan, Rong Yu
The equipment maintenance support scenario should been made according to equipment mission requirements and maintenance support resource allocation standards, whose contents includes: repair type , maintenance principle, maintenance level, maintenance support personnel number and kinds, spare parts, maintenance support equipment type and quantity and maintenance processes.
Intelligent equipment layer contains all kinds of the equipment and devices which can be identified by information, intelligent equipment’s information interfaces, which can transmitted equipment information, such as equipment name, number …etc,to the data acquisition layer automatically .The on-site maintenance and data acquisition layer includs interactive electronic manuals management, depot-level maintenance and remote personnel maintenance, training, assembly, disassembly.
The division principle is that granule division is used in the system and fine-grained component combination of coarse-grained components when the systems between need to call.
Intelligent equipment layer contains all kinds of the equipment and devices which can be identified by information, intelligent equipment’s information interfaces, which can transmitted equipment information, such as equipment name, number …etc,to the data acquisition layer automatically .The on-site maintenance and data acquisition layer includs interactive electronic manuals management, depot-level maintenance and remote personnel maintenance, training, assembly, disassembly.
The division principle is that granule division is used in the system and fine-grained component combination of coarse-grained components when the systems between need to call.
Online since: April 2012
Authors: Niels Hansen, Tian Bo Yu
Experimental
The commercial purity aluminum AA1050, with an initial grain size of about 100 µm and a chemical composition of 99.5Al-0.25Fe-0.15Si (wt %), was cold rolled to a true strain of 5.5 (99.6% reduction in thickness).
A number of small samples were cut and subjected to an isothermal annealing heat treatment at temperatures of 140, 160, 180, 200 or 220°C over time intervals ranging from 1 minute to 51 days.
The recrystallized grains appear brighter than the recovered matrix.
The lower activation energy at the beginning of recovery may be related to the high stored energy in the heavily deformed material, where a larger number of crystal defects (e.g. dislocations and dislocation boundaries) are present.
A number of small samples were cut and subjected to an isothermal annealing heat treatment at temperatures of 140, 160, 180, 200 or 220°C over time intervals ranging from 1 minute to 51 days.
The recrystallized grains appear brighter than the recovered matrix.
The lower activation energy at the beginning of recovery may be related to the high stored energy in the heavily deformed material, where a larger number of crystal defects (e.g. dislocations and dislocation boundaries) are present.
Online since: March 2013
Authors: Jing Wu Zheng, Yao Ying, Liang Qiao, Li Qiang Jiang, Wei Cai, Zhi Liang Wang, Sheng Lei Che
The Thermo ARL SCINTAG X'TRA X-ray diffraction (XRD) were used to research the crystalline grain .
From the figure 5(a), we can know that some silver particles were deposited on the carbon surface, but there appear a large number of massive silver particles in the solution.
Parts of carbon surface without silver particles deposition and a large number of reunited silver grains were appeared in the solution, as show in Fig.5 (d).
From the figure 5(a), we can know that some silver particles were deposited on the carbon surface, but there appear a large number of massive silver particles in the solution.
Parts of carbon surface without silver particles deposition and a large number of reunited silver grains were appeared in the solution, as show in Fig.5 (d).
Online since: February 2009
Authors: A.I. Inegbenebor
.< = + 3cm
Sta. 1 to
10m:
Gray mdst with distinctive spheroid frac; no sign
dbg; Weather pale tan, and grain of qz, field total
20%; both silt and clay abnt in matrix.
Sta. 1 + 10m to sta 3: ss; gray (weather tan), in beds 10cm-1m thick, interbeds carb silty mdst are 10cm-2m in thick, ss mainly med-grained but base of thicker beds course, locally pebby.
D VGB (Sesamum (Acta) sorghum soyabeans) Ca Pb Mg Zn Ca Pb Mg Zn 0.180 0.07 0.11 0.04 0.30 0.2 0.1 0.1 0.183 0.05 0.13 0.06 0.50 0.11 0.3 0.4 0.185 0.05 0.11 0.05 0.80 0.32 0.4 0.51 OBS 0.191 0.07 0.15 0.08 1.00 0.33 0.2 0.11 0.192 0.08 0.14 0.07 1.20 0.35 0.05 0.50 0.199 0.07 0.14 0.07 1.31 0.53 0.15 0.34 50.20 50.15 50.10 50.05 50.00 49.95 49.85 49.80 1 2 3 4 5 6 7 8 9 10 11 12 13 Sample number Upper action value Upper warning limit Lower action value Lower warning limit Target value C a L C I u m c o n t e n t Upper action line Upper warning value R a n g e Lower warning limit 0.6 1 2 3 4 5 6 7 8 9 10 11 0.5 0.4 0.3 0.2 0.1 Sample number calcium content in localities
Sta. 1 + 10m to sta 3: ss; gray (weather tan), in beds 10cm-1m thick, interbeds carb silty mdst are 10cm-2m in thick, ss mainly med-grained but base of thicker beds course, locally pebby.
D VGB (Sesamum (Acta) sorghum soyabeans) Ca Pb Mg Zn Ca Pb Mg Zn 0.180 0.07 0.11 0.04 0.30 0.2 0.1 0.1 0.183 0.05 0.13 0.06 0.50 0.11 0.3 0.4 0.185 0.05 0.11 0.05 0.80 0.32 0.4 0.51 OBS 0.191 0.07 0.15 0.08 1.00 0.33 0.2 0.11 0.192 0.08 0.14 0.07 1.20 0.35 0.05 0.50 0.199 0.07 0.14 0.07 1.31 0.53 0.15 0.34 50.20 50.15 50.10 50.05 50.00 49.95 49.85 49.80 1 2 3 4 5 6 7 8 9 10 11 12 13 Sample number Upper action value Upper warning limit Lower action value Lower warning limit Target value C a L C I u m c o n t e n t Upper action line Upper warning value R a n g e Lower warning limit 0.6 1 2 3 4 5 6 7 8 9 10 11 0.5 0.4 0.3 0.2 0.1 Sample number calcium content in localities
Online since: February 2019
Authors: Nikita A. Zavartsev, Nadezhda T. Kareva
Diphase (α + β) titanium alloys are characterized by a high tendency to overheat: when the boundary (α + β) / β is exceeded, intensive grain growth is observed.
It is not possible to eliminate superheating in the finish part of heat treatment: a small phase hardening of the α↔β transition is insufficient for the development of β-grain recrystallization [2, 3].
At the beginning, the long plates of the α-phase are fragmented into smaller ones, acquire a rounded shape, the number of particles decreases (Fig. 1 a, b, c), then the α-phase completely disappears (Fig. 1 d).
Reduction of the experimental determination process Tpt with the help of method trial hardening is achieved by decreasing of the number of samples to one.
It is not possible to eliminate superheating in the finish part of heat treatment: a small phase hardening of the α↔β transition is insufficient for the development of β-grain recrystallization [2, 3].
At the beginning, the long plates of the α-phase are fragmented into smaller ones, acquire a rounded shape, the number of particles decreases (Fig. 1 a, b, c), then the α-phase completely disappears (Fig. 1 d).
Reduction of the experimental determination process Tpt with the help of method trial hardening is achieved by decreasing of the number of samples to one.