Experimental and 3D MPFEM simulation study on the green density of Ti–6Al–4V powder compact during uniaxial high velocity compaction

2020 ◽  
Vol 817 ◽  
pp. 153226
Author(s):  
Jian Zhou ◽  
Chenyu Zhu ◽  
Wei Zhang ◽  
Wentao Ai ◽  
Xuejie Zhang ◽  
...  
Keyword(s):  
Simulation Study ◽  
High Velocity ◽  
Powder Compact ◽  
Green Density ◽  
High Velocity Compaction

scholarly journals A Control Method of High Impact Energy and Cosimulation in Powder High-Velocity Compaction

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Dongdong You ◽  
Dehui Liu ◽  
Hangjian Guan ◽  
Qingyun Huang ◽  
Zhiyu Xiao ◽  
...  
Keyword(s):  
Impact Energy ◽  
High Velocity ◽  
Mechanical Energy ◽  
High Impact ◽  
Experimental Results ◽  
Hydraulic Control ◽  
Green Density ◽  
High Impact Energy ◽  
High Velocity Compaction ◽  
The Impact

To enhance the impact energy of powder high-velocity compaction (HVC) and thus improve the green density and mechanical properties of the resulting compacts, a mechanical energy storage method using combination disc springs is proposed. The high impact energy is achieved by modifying existing equipment, and the hydraulic control system is developed to implement the automatic control of the energy produced from the disc springs. An interdisciplinary cosimulation platform is established using the ADAMS, AMESim, and LabVIEW software packages to perform the interactive control of the simulation process and the real-time feedback of the simulation results. A mechanical-hydraulic cosimulation of the energy control virtual prototype of the testing machine is conducted using this platform. The influence of the impact energy on the green density is studied according to the HVC experimental results of the iron-based powders, and then, the green compact with the higher relative density is produced. The experimental results indicate that the energy enhancement method using the combination disc springs is reasonable and that the hydraulic control scheme is reliable.

High Velocity Compaction of 316L Stainless Powder

2010 ◽  
Vol 44-47 ◽  
pp. 2993-2997 ◽  
Author(s):  
Jin Chen ◽  
Zhi Yu Xiao ◽  
Chao Jie Li ◽  
San Cai Deng ◽  
Tung Wai Leo Ngai ◽  
...  
Keyword(s):  
Impact Energy ◽  
High Velocity ◽  
Delay Time ◽  
Green Density ◽  
Single Impact ◽  
Impact Process ◽  
Ejection Force ◽  
High Velocity Compaction ◽  
Total Impact ◽  
Double Impact

High velocity compaction technology was used to press 316L stainless powders. Effects of impact times on stress wave, green density and ejection force were analyzed. It was found that under the same total impact energy, the first loading time and the actuation duration of the second impact in double impact process were longer when compared with single impact process, while the first delay time was shorter. Furthermore, the green density of compacts prepared by double impact was greater than that prepared by single impact, but no obvious variation in maximum ejection force can be observed between single impact and double impact process.

Compaction Experiment on the Newly Designed Warm High Velocity Compaction Equipment

2010 ◽  
Vol 139-141 ◽  
pp. 485-488 ◽  
Author(s):  
Cui Yong Tang ◽  
Zhi Yu Xiao ◽  
Jin Chen ◽  
Chao Jie Li ◽  
Tung Wai Leo Ngai
Keyword(s):  
Powder Metallurgy ◽  
High Velocity ◽  
Hydraulic Cylinder ◽  
Gravitational Potential Energy ◽  
Green Density ◽  
Densification Mechanism ◽  
Forming Technology ◽  
Preliminary Study ◽  
High Velocity Compaction ◽  
Powder Compacts

In order to develop high density powder metallurgy forming technology, a new concept combining high velocity compaction and warm compaction called warm high velocity compaction (WHVC) was presented. A new warm high velocity compaction forming equipment which adopts gravitational potential energy instead of hydraulic cylinder as hammer driver was designed. By means of the newly developed equipment, a preliminary study on warm high velocity compaction was performed. 316L stainless powder compacts with green density of 7.47 g/cm3 were obtained; the density is much higher than those prepared by conventional high velocity compaction. These results demonstrate that the newly designed equipment can basically meet the demand of warm high velocity compaction and the new forming method is superior to the conventional high velocity compaction. In addition, Densification mechanism of WHVC was also discussed.

scholarly journals Effects of Sintering Temperature on Densification, Microstructure and Mechanical Properties of Al-Based Alloy by High-Velocity Compaction

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 218
Author(s):  
Xianjie Yuan ◽  
Xuanhui Qu ◽  
Haiqing Yin ◽  
Zaiqiang Feng ◽  
Mingqi Tang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Velocity ◽  
Sintered Density ◽  
Sintering Temperature ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron ◽  
High Velocity Compaction ◽  
Sintered Temperature

This present work investigates the effects of sintering temperature on densification, mechanical properties and microstructure of Al-based alloy pressed by high-velocity compaction. The green samples were heated under the flow of high pure (99.99 wt%) N2. The heating rate was 4 °C/min before 315 °C. For reducing the residual stress, the samples were isothermally held for one h. Then, the specimens were respectively heated at the rate of 10 °C/min to the temperature between 540 °C and 700 °C, held for one h, and then furnace-cooled to the room temperature. Results indicate that when the sintered temperature was 640 °C, both the sintered density and mechanical properties was optimum. Differential Scanning Calorimetry, X-ray diffraction of sintered samples, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, and Transmission Electron Microscope were used to analyse the microstructure and phases.

scholarly journals Effects of Compaction Velocity on the Sinterability of Al-Fe-Cr-Ti PM Alloy

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 3005 ◽  
Author(s):  
Xianjie Yuan ◽  
Xuanhui Qu ◽  
Haiqing Yin ◽  
Zhenwei Yan ◽  
Zhaojun Tan
Keyword(s):  
Mechanical Properties ◽  
High Velocity ◽  
Alloy Powder ◽  
Sintered Density ◽  
Ti Alloy ◽  
Maximum Elongation ◽  
Nitrogen Gas ◽  
High Velocity Compaction ◽  
Ti Powder ◽  
Particle Boundary

In this research, the effects of the compaction velocity on the sinterability of the Al–Fe–Cr–Ti powder metallurgy (PM) alloy by high velocity compaction were investigated. The Al–Fe–Cr–Ti alloy powder was compacted with different velocities by high velocity compaction and then sintered under a flow of high pure (99.999 wt%) nitrogen gas. Results indicated that both the sintered density and mechanical properties increased with increasing compaction velocity. By increasing the compaction velocity, the shrinkage of the sintered samples decreased. A maximum sintered density of 2.85 gcm−3 (relative density is 98%) was obtained when the compaction velocity was 9.4 ms−1. The radial and axial shrinkage were controlled to less than 1% at a compaction velocity of 9.4 ms−1. At a compaction velocity of 9.4 ms−1, sintered compacts with an ultimate tensile strength of 222 MPa and a yield strength of 160 MPa were achieved. The maximum elongation was observed to be 2.6%. The enhanced tensile properties of the Al–Fe–Cr–Ti alloy were mainly due to particle boundary strengthening.

Quantitative investigation on force chain lengths during high velocity compaction of ferrous powder

2019 ◽  
Vol 33 (10) ◽  
pp. 1950113 ◽  
Author(s):  
Wei Zhang ◽  
Jian Zhou ◽  
Xuejie Zhang ◽  
Yan Zhang ◽  
Kun Liu
Keyword(s):  
High Velocity ◽  
Pearson Correlation ◽  
Quantitative Characteristic ◽  
Correlation Coefficients ◽  
High Strength ◽  
Force Chain ◽  
Force Chains ◽  
Low Probability ◽  
High Velocity Compaction ◽  
Chain Lengths

Force chains play an important role in linking the macro- and micro-mechanisms of powder in high velocity compaction (HVC). Force chain lengths, as an important quantitative characteristic, can describe the geometry of force chains. In this study, force chain lengths and their relation to other force chain characteristics in HVC were investigated by discrete element method. Results revealed that force chain length decreased and it can be related to the densification process of ferrous powder in HVC. Moreover, long force chains extended from top to bottom and may play a major role in supporting load, although the percentage of long force chains was low. Probability density functions of force chain lengths further showed the exponential decay. The proportion of short force chains increased and the proportion of long force chains decreased. Long force chains had high strength and can be aligned to the direction of the external load, but force chain lengths did not have clear relation to straightness. These relations were confirmed by Pearson correlation coefficients.

Characteristic Analysis of the Stress Propagation of Metal Powder in High Velocity Compaction Using DEM

2020 ◽  
Vol 89 (4) ◽  
pp. 044602
Author(s):  
Wei Zhang ◽  
Kun Liu ◽  
Jian Zhou ◽  
Rongxin Chen ◽  
Ning Zhang ◽  
...  
Keyword(s):  
Metal Powder ◽  
High Velocity ◽  
Characteristic Analysis ◽  
Stress Propagation ◽  
High Velocity Compaction
Sign in / Sign up

Export Citation Format

Share Document