Analysis and suppression of flange wrinkling in AHSS chain-die forming channels with a curved axis

The effect of hydrogenation on structure and properties of TC21 alloy by die forming and sintering using hydrogenated powder was researched by means of the room-temperature die forming and sintering in protection air to produce titanium alloy. The results show that the structure of TC21 titanium sintered body using hydrogenated powder with hydrogen content of 0.39 wt% by die forming and sintering is thinner and the density is higher than the others. The compression strength and compressive yield strength of TC21 sintered body with hydrogen content of 0.39 wt% are well. With hydrogen content increasing, the structure of TC21 production using hydrogenated powder by die forming and sintering gets well and the grain size becomes smaller. After annealing, the structure of TC21 titanium production gets more uniformity and refinement obviously, and the hydrogen content of TC21 alloy safety state is achieved. In the end, the density and mechanical property of TC21 titanium alloy sintered body with hydrogen content of 0.39wt % is the best.

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Obtaining Biologically Active Polypropylene Fibrous Materials

Materials Science Forum ◽

10.4028/www.scientific.net/msf.992.764 ◽

2020 ◽

Vol 992 ◽

pp. 764-769

Author(s):

Sergey Bordunov ◽

Olga Galtseva ◽

Inna Plotnikova

Keyword(s):

Ion Exchange ◽

Biologically Active ◽

Polymer Fibers ◽

Polypropylene Fibers ◽

Fibrous Materials ◽

Centrifugal Forces ◽

Polypropylene Melt ◽

Die Forming

The paper presents the results of the development of the technology of centrifugal-die forming of biologically active fibrous materials. The modification of biologically active polypropylene fibers was carried out directly at the process of their production in the field of centrifugal forces of rotating reactor during their molding from polypropylene melt. The properties of the obtained ion-exchange and biologically active polymer fibers are studied. It is shown that obtained and modified by the centrifugal-die method polypropylene fibers can be used as biologically active fibers.

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Performance of Thermo-Mechanically Processed AA7075 Alloy at Elevated Temperatures—From Microstructure to Mechanical Properties

Metals ◽

10.3390/met10070884 ◽

2020 ◽

Vol 10 (7) ◽

pp. 884 ◽

Cited By ~ 1

Author(s):

Seyed Vahid Sajadifar ◽

Emad Scharifi ◽

Ursula Weidig ◽

Kurt Steinhoff ◽

Thomas Niendorf

Keyword(s):

Mechanical Properties ◽

Elevated Temperatures ◽

Tensile Tests ◽

Uniaxial Tensile ◽

Forming Process ◽

Softening Mechanism ◽

Rate Dependent ◽

Heat Treated ◽

Different Temperatures ◽

Die Forming

This study focuses on the high temperature characteristics of thermo-mechanically processed AA7075 alloy. An integrated die forming process that combines solution heat treatment and hot forming at different temperatures was employed to process the AA7075 alloy. Low die temperature resulted in the fabrication of parts with higher strength, similar to that of T6 condition, while forming this alloy in the hot die led to the fabrication of more ductile parts. Isothermal uniaxial tensile tests in the temperature range of 200–400 °C and at strain rates ranging from 0.001–0.1 s−1 were performed on the as-received material, and on both the solution heat-treated and the thermo-mechanically processed parts to explore the impacts of deformation parameters on the mechanical behavior at elevated temperatures. Flow stress levels of AA7075 alloy in all processing states were shown to be strongly temperature- and strain-rate dependent. Results imply that thermo-mechanical parameters are very influential on the mechanical properties of the AA7075 alloy formed at elevated temperatures. Microstructural studies were conducted by utilizing optical microscopy and a scanning electron microscope to reveal the dominant softening mechanism and the level of grain growth at elevated temperatures.

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