The Roles of Process Parameters on Structures and Mechanical Properties of Polypropylene/Clay Nanocomposites

Multi-material-design offers high potential for weight saving and optimization of engineering structures but inherits challenges as well, especially robust joining methods and long-term properties of hybrid structures. The application of joining techniques like ultrasonic welding allows a very efficient design of multi-material-components to enable further use of material specific advantages and are superior concerning mechanical properties.The Institute of Materials Science and Engineering of the University of Kaiserslautern (WKK) has a long-time experience on ultrasonic welding of dissimilar materials, for example different kinds of CFRP, light metals, steels or even glasses and ceramics. The mechanical properties are mostly optimized by using ideal process parameters, determined through statistical test planning methods.This gained knowledge is now to be transferred to application in aviation industry in cooperation with CTC GmbH and Airbus Operations GmbH. Therefore aircraft-related materials are joined by ultrasonic welding. The applied process parameters are recorded and analyzed in detail to be interlinked with the resulting mechanical properties of the hybrid joints. Aircraft derived multi-material demonstrators will be designed, manufactured and characterized with respect to their monotonic and fatigue properties as well as their resistance to aging.

Download Full-text

Effect of Friction Stir Process Parameters on Mechanical Properties of Chrome Containing Leather Waste Reinforced Aluminium Based Composite

International Journal of Precision Engineering and Manufacturing-Green Technology ◽

10.1007/s40684-021-00312-z ◽

2021 ◽

Author(s):

Shashi Prakash Dwivedi ◽

Rajeev Agrawal ◽

Shubham Sharma

Keyword(s):

Mechanical Properties ◽

Process Parameters ◽

Friction Stir Process ◽

Friction Stir ◽

Leather Waste

Download Full-text

Effect of Organic Modifier Types on the Physical–Mechanical Properties and Overall Migration of Post-Consumer Polypropylene/Clay Nanocomposites for Food Packaging

Polymers ◽

10.3390/polym13091502 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1502

Author(s):

Eliezer Velásquez ◽

Sebastián Espinoza ◽

Ximena Valenzuela ◽

Luan Garrido ◽

María José Galotto ◽

...

Keyword(s):

Mechanical Properties ◽

Food Packaging ◽

Clay Nanocomposites ◽

Organic Modifier ◽

Thermal And Mechanical Properties ◽

Chemical Safety ◽

Elongation At Break ◽

Fatty Food ◽

Recycled Plastics ◽

Thermal Stability Of

The deterioration of the physical–mechanical properties and loss of the chemical safety of plastics after consumption are topics of concern for food packaging applications. Incorporating nanoclays is an alternative to improve the performance of recycled plastics. However, properties and overall migration from polymer/clay nanocomposites to food require to be evaluated case-by-case. This work aimed to investigate the effect of organic modifier types of clays on the structural, thermal and mechanical properties and the overall migration of nanocomposites based on 50/50 virgin and recycled post-consumer polypropylene blend (VPP/RPP) and organoclays for food packaging applications. The clay with the most hydrophobic organic modifier caused higher thermal stability of the nanocomposites and greater intercalation of polypropylene between clay mineral layers but increased the overall migration to a fatty food simulant. This migration value was higher from the 50/50 VPP/RPP film than from VPP. Nonetheless, clays reduced the migration and even more when the clay had greater hydrophilicity because of lower interactions between the nanocomposite and the fatty simulant. Conversely, nanocomposites and VPP/RPP control films exhibited low migration values in the acid and non-acid food simulants. Regarding tensile parameters, elongation at break values of PP film significantly increased with RPP addition, but the incorporation of organoclays reduced its ductility to values closer to the VPP.

Download Full-text

Influence of Tool Geometry and Process Parameters on the Properties of Friction Stir Spot Welded Multiple (AA 5754 H111) Aluminium Sheets

Materials ◽

10.3390/ma14051157 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1157

Author(s):

Danka Labus Zlatanovic ◽

Sebastian Balos ◽

Jean Pierre Bergmann ◽

Stefan Rasche ◽

Milan Pecanac ◽

...

Keyword(s):

Mechanical Properties ◽

Process Parameters ◽

Spot Welding ◽

Minimum Energy ◽

Tool Geometry ◽

Friction Stir ◽

Minimum Energy Consumption ◽

Punch Test ◽

Wide Range ◽

Lap Welding

Friction stir spot welding is an emerging spot-welding technology that offers opportunities for joining a wide range of materials with minimum energy consumption. To increase productivity, the present work addresses production challenges and aims to find solutions for the lap-welding of multiple ultrathin sheets with maximum productivity. Two convex tools with different edge radii were used to weld four ultrathin sheets of AA5754-H111 alloy each with 0.3 mm thickness. To understand the influence of tool geometries and process parameters, coefficient of friction (CoF), microstructure and mechanical properties obtained with the Vickers microhardness test and the small punch test were analysed. A scanning acoustic microscope was used to assess weld quality. It was found that the increase of tool radius from 15 to 22.5 mm reduced the dwell time by a factor of three. Samples welded with a specific tool were seen to have no delamination and improved mechanical properties due to longer stirring time. The rotational speed was found to be the most influential parameter in governing the weld shape, CoF, microstructure, microhardness and weld efficiency. Low rotational speeds caused a 14.4% and 12.8% improvement in joint efficiency compared to high rotational speeds for both tools used in this investigation.

Download Full-text

Process parameters and mechanical properties of SAPH440 steel in pulse arc welding with different heat inputs

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/770/1/012104 ◽

2020 ◽

Vol 770 ◽

pp. 012104

Author(s):

S F Liang ◽

L X Chi ◽

X Z Gao ◽

B L Yan

Keyword(s):

Mechanical Properties ◽

Process Parameters ◽

Arc Welding

Download Full-text

Deformation and Fracture Behaviors in the Freestanding APS-TBC - Effects of Process Parameters and Thermal Exposure

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.1935 ◽

2007 ◽

Vol 353-358 ◽

pp. 1935-1938 ◽

Cited By ~ 3

Author(s):

Yasuhiro Yamazaki ◽

T. Kinebuchi ◽

H. Fukanuma ◽

N. Ohno ◽

K. Kaise

Keyword(s):

Mechanical Properties ◽

Process Parameters ◽

Gas Turbines ◽

Thermal Exposure ◽

Substrate Material ◽

Process Variables ◽

Microstructural Investigation ◽

Deformation And Fracture ◽

Industrial Gas Turbines ◽

Tbc Systems

Thermal barrier coatings (TBCs), that reduce the temperature in the underlying substrate material, are an essential requirement for the hot section components of industrial gas turbines. Recently, in order to take full advantage of the potential of the TBC systems, experimental and analytical investigations in TBC systems have been performed. However there is a little information on the deformation behavior of the top coating. In addition, the effects of the thermal exposure and the process parameters on the mechanical properties of the top coating have never been clarified. From these backgrounds, the effects of the process variables in APS and the thermal exposure on the mechanical properties were investigated in order to optimize the APS process of top coatings. The experimental results indicated that the mechanical properties of the APS-TBC, i.e. the tensile strength and the elastic modulus, were significantly changed by the process variables and the long term thermal exposure. The microstructural investigation was also carried out and the relationship between the mechanical properties and the porosity was discussed.

Download Full-text

Mechanical properties optimization of the steering column based on multi-objective optimization design

Advances in Mechanical Engineering ◽

10.1177/1687814016682941 ◽

2016 ◽

Vol 8 (12) ◽

pp. 168781401668294 ◽

Cited By ~ 1

Author(s):

Si Chen ◽

Zhaohui Wang ◽

Mi Lv

Keyword(s):

Mechanical Properties ◽

Process Parameters ◽

Optimization Design ◽

Strain Difference ◽

Optimization Method ◽

Equivalent Strain ◽

Multi Objective Optimization ◽

Optimal Process ◽

Multi Objective ◽

Initial Results

The mechanical properties of the steering column have a significant influence on the comfort and stability of a vehicle. In order for the mechanical properties to be improved, the rotary swaging process of the steering column is studied in this article. The process parameters, including axial feed rate, hammerhead speed, and hammerhead radial reduction, are systematically analyzed and optimized based on a multi-objective optimization design. The response surface methodology and the genetic algorithm are employed for optimal process parameters to be obtained. The maximum damage value, the maximum forming load, and the equivalent strain difference obtained with the optimal process parameters are, respectively, decreased by 30.09%, 7.44%, and 57.29% compared to the initial results. The comparative results present that the quality of the steering column is improved. The torque experiments and fatigue experiments are conducted with the optimal steering column. The maximum torque is measured to be 260 NM, and the service life is measured to be 2 weeks (40 NM, 2500 times), which are, respectively, increased by 8.3% and 8.69% compared to the initial results. The above results display that the mechanical properties of the steering column are optimized to verify the feasibility of the multi-objective optimization method.

Download Full-text