Analysis of individual and interaction effects of processing parameters on wet grinding performance in ball milling of alumina ceramics using statistical methods

Streckziehen keramischer Grünfolien*/Stretch drawing of ceramic green tapes - Investigation of the factors influencing to the stretch drawing capacity of ceramic green tapes

wt Werkstattstechnik online ◽

10.37544/1436-4980-2016-11-12-69 ◽

2016 ◽

Vol 106 (11-12) ◽

pp. 847-850

Author(s):

Q. Spiller ◽

M. Baumeister ◽

J. Prof. Fleischer

Keyword(s):

Statistical Methods ◽

Three Dimensional ◽

Interaction Effects ◽

Powder Technology ◽

Factors Influencing ◽

Statistische Methoden ◽

Main Effects

Im Bereich der Pulvertechnologie stellt das Streckziehen keramischer Grünfolien eine wirtschaftliche Möglichkeit dar, dreidimensionale Halbzeuge herzustellen. Im Rahmen des AiF-Projekts „Inka“ werden die Einflüsse der Prozess- und Geometrieparameter auf die Streckziehfähigkeit von keramischen Grünfolien aus dem Werkstoff ZrO2 experimentell untersucht. Dabei kommen statistische Methoden zur Ermittlung der Haupt- und Wechselwirkungseffekte zum Einsatz.   In the field of powder technology stretch drawing is an economic way to produce three-dimensional semi-finished products. In the context of the AIF Project “Inka“ the influences of process and geometry parameters are experimental examined on stretch drawing capacity of ceramic green tapes of material ZrO2. Statistical methods are used to find out main effects and interaction effects.

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Effects of Ball Milling Processing Conditions and Alloy Components on the Synthesis of Cu-Nb and Cu-Mo Alloys

Materials ◽

10.3390/ma12081224 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1224 ◽

Cited By ~ 1

Author(s):

Xuekun Shang ◽

Xitao Wang ◽

Silian Chen

Keyword(s):

Size Distribution ◽

Ball Milling ◽

Oxidation Process ◽

Processing Parameters ◽

Processing Conditions ◽

Cold Welding ◽

Immiscible Alloys ◽

Ball Size ◽

Milling Method

The effects of processing parameters in ball milling and the different behaviors of Cu-Nb and Cu-Mo alloys during milling were investigated. High powder yields can be obtained by changing the BPR value and ball size distribution and no clear dependence of BPR value on powder yield can be found from the experiment results. The addition of oxygen can largely reduce the effect of excessive cold welding during ball milling. A “two-step” ball milling method was introduced to evaluate the different evolution processes and morphologies in different alloys. With 8 h pre-milling, this method considerably benefits the oxidation process of Mo and shows its promising potential in the synthesis of immiscible alloys. Based on the experiment results and analysis, we suggest that the different behaviors of Cu-Nb and Cu-Mo alloys are related to the shear modules and different tendencies to be oxidized.

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Effects of Processing Conditions on Laser Direct Deposited Alumina Ceramics

Volume 1: Additive Manufacturing; Advanced Materials Manufacturing; Biomanufacturing; Life Cycle Engineering; Manufacturing Equipment and Automation ◽

10.1115/msec2020-8260 ◽

2020 ◽

Author(s):

John M. Pappas ◽

Xiangyang Dong

Keyword(s):

Grain Size ◽

Processing Parameters ◽

Thin Wall ◽

Processing Conditions ◽

Single Track ◽

Alumina Ceramics ◽

Direct Deposition ◽

Average Grain Size ◽

Scan Speed ◽

Laser Direct Deposition

Abstract Additive manufacturing (AM) of high-quality inherently brittle ceramics via laser direct deposition, also known as laser engineered net shaping, is challenging due to high thermal gradients, thermally induced cracks, and porosity, typically accompanied by low powder usage efficiency. It is necessary to have an improved understanding of the effects of processing conditions on the fabricated ceramic parts. In this study, alumina ceramics were fabricated with commercial alumina powders. In particular, this paper studied the effect of laser power and scan speed on single track geometries, thin-wall morphology, grain size, density, and powder efficiency during laser direct deposition of alumina ceramics. A single-track parametric study was first conducted to determine the range of processing parameters that produce quality single-tracks and to aid in matching the z-increment with layer thicknesses. The results showed that increased scan speeds promoted significant grain refinement. Average grain size was reduced by nearly 50% when scan speed was increased from 1000 mm/min to 5000 mm/min. On the other hand, densification reached a maximum of 98% at a scan speed of 1000 mm/min with a slight decrease in density was observed at higher speeds. This indicated a trade-off between porosity and grain size when altering the laser scan speed. Significant advantages of using CO2 lasers for AM of ceramics was also demonstrated with powder usage efficiencies reaching nearly 90% under optimized processing conditions.

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Study on Grinding Technology for Seafloor Mineral Processing

Volume 3: Materials Technology; Ocean Space Utilization ◽

10.1115/omae2013-10756 ◽

2013 ◽

Author(s):

Yasuharu Nakajima ◽

Joji Yamamoto ◽

Shigeo Kanada ◽

Sotaro Masanobu ◽

Ichihiko Takahashi ◽

...

Keyword(s):

Ball Mill ◽

Mineral Resources ◽

Mineral Processing ◽

Hydrothermal Fluids ◽

Small Scale ◽

Pressure Condition ◽

Massive Sulfides ◽

Rotation Rates ◽

Wet Grinding ◽

Grinding Performance

Seafloor Massive Sulfides (SMSs), which are formed by precipitates from hydrothermal fluids vented from seafloor, have been expected as one of mineral resources to be developed. The authors have proposed the concept of seafloor mineral processing for SMS mining, where valuable minerals contained in SMS ores are separated on seafloor. To apply a ball mill to the grinding unit for seafloor mineral processing, grinding experiments were carried out using a small-scale ball mill applicable to high-pressure condition. In the experiments, wet grinding and water-filled grinding of size-classified silica sands were carried out at three rotation rates to compare the grinding performance in both cases. In both cases, the silica sands were finely ground. The measurement of particle size of samples from the experiments showed that water-filled grinding had comparable grinding performance to wet grinding while the suitable rotation rate for water-filled grinding shifted to higher than that for wet grinding. This result suggests the possibility of water-filled grinding for seafloor mineral processing. If water-filled grinding can be employed for the grinding unit, the structure of the grinding unit would be simplified in comparison with wet grinding that leads to the saving of grinding costs.

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Study on the Effect of Standoff Distance on Processing Performance of Alumina Ceramics in Two Modes of Abrasive Waterjet Turning Patterns

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.797.21 ◽

2013 ◽

Vol 797 ◽

pp. 21-26 ◽

Cited By ~ 4

Author(s):

Dun Liu ◽

Chuan Zhen Huang ◽

Jun Wang ◽

Hong Tao Zhu ◽

Peng Yao ◽

...

Keyword(s):

Processing Parameters ◽

Impact Angle ◽

Machining Process ◽

Radial Mode ◽

Standoff Distance ◽

Abrasive Waterjet ◽

Alumina Ceramics ◽

Depth Of Penetration ◽

Cylindrical Parts ◽

And Performance

Abrasive waterjet (AWJ) turning is an emerging technology, which plays an important role in machining cylindrical parts with the distinct advantages of negligible thermal effects and extremely low cutting force. This paper presents an experimental study of abrasive waterjet turning (AWJT) of Al2O3ceramics. The machining process and performance in terms of the depth of penetration (DOP), surface roughness (Ra) and actual impact angle (β) are discussed to understand the effect of standoff distance (SOD) on the processing performance at two different turning modes. Based on the results of these investigations, there is a significant change ofDOPandRaat differentSODin radial mode turning and the optimalSODof gaining maximumDOPand the minimumRais about 5.5mm.However, theDOPis nearly independent on theSODin offset mode turning. SmallerRaandDOPcan be obtained in offset mode. Furthermore, the results indicate that the roundness error of cylinder parts is probably improved with the properSODinterval in radial mode turning and it is suitable for machining cylinder part with considerably different radial size. The offset mode turning as the next operation after radial mode turning is recommended to process workpiece with excellent roundness. In this way, by understanding the effect ofSODon processing alumina ceramics, the paper establishes a good basis for developing strategies for optimizing processing parameters in order to generate the desired part geometry and achieve better surface quality.

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