Effect of surface defects in light press aluminum extrusions on aerospace manufacturingSorenson, E. Proc. Fifth International Aluminum Extrusion Technology Sem., Chicago, Illinois, USA, 19–22 May 1992, Vol I (The Aluminum Association, Washington, DC, USA, 1992) pp 521–525

The influence of local inner die cooling on the heat balance in hot aluminum extrusion was investigated. For the manufacturing of the die with cooling channels close to the forming zone, the layer-laminated manufacturing method was applied. The new tooling technology was applied in order to decrease the profiles exit temperature and to avoid thermally induced surface defects with the aim to raise the productivity in hot aluminum extrusion processes. Numerical and experimental investigations revealed that, while maintaining the exit temperature of the extrudate, a distinct increase of the production speed up to 300% can be realized, while the extrusion force increases only slightly. An effect on the profiles microstructure was also detected. By applying die cooling, grain coarsening can be significantly limited or even be avoided.

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The Effect of Surface Defects on Mechanical Properties of Powder Forged Material.

Journal of the Japan Society of Powder and Powder Metallurgy ◽

10.2497/jjspm.41.285 ◽

1994 ◽

Vol 41 (3) ◽

pp. 285-288

Author(s):

Kazuhiko Takahashi ◽

Eisuke Hoshina

Keyword(s):

Mechanical Properties ◽

Surface Defects ◽

Effect Of Surface

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Aluminum Extrusion Technology

10.31399/asm.tb.aet.9781627083362 ◽

2000 ◽

Author(s):

Pradip K. Saha

Keyword(s):

Theory And Practice ◽

Die Design ◽

Hard Alloys ◽

Aluminum Extrusion ◽

Statistical Process ◽

Print Version ◽

Strain And Strain Rate ◽

Friction Pressure ◽

Key Variables ◽

Extrusion Technology

Aluminum Extrusion Technology covers the theory and practice of extrusion and its application in the production of aluminum alloy parts. The first few chapters discuss the mechanics and thermodynamics of direct and indirect extrusion processes and the effect of key variables such as strain and strain rate, friction, pressure, flow stress, and temperature. Subsequent chapters explain how to implement and maintain industrial-scale aluminum extrusion processes. The chapters cover extrusion presses and equipment, tooling and die design, billet casting, and process control. They also provide information on the extrusion characteristics of soft, medium, and hard alloys and discuss the use of statistical process and quality control. For information on the print version, ISBN 978-0-87170-644-7, follow this link.

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Effect of surface defects on the fatigue behavior of a cast TiAl alloy.

MRS Proceedings ◽

10.1557/proc-646-n5.44.1 ◽

2000 ◽

Vol 646 ◽

Author(s):

M. Nazmy ◽

M. Staubli ◽

G. Onofrio ◽

V. Lupinc

Keyword(s):

Tial Alloy ◽

High Cycle Fatigue ◽

Surface Defects ◽

Fatigue Behavior ◽

Impact Resistance ◽

Economic Life ◽

Crack Advance ◽

Crack Growth Behavior ◽

Engine Components ◽

Effect Of Surface

ABSTRACTThe effect of surface defects on the performance of TiAl-base alloys is an issue of importance in contemplating their application into engine components. Due to the relatively low ductility and low impact resistance of gamma alloys the validation of models for estimating economic life and for safe-life approaches employed for components becomes of great importance. Surface defects can be attributed to various sources during the manufacturing or handling of the components. In fact, little is known about the detrimental effects of surface defects on gamma alloys. In the present study, the effect of artificially introduced surface defects, on the high cycle fatigue behavior of the Ti-47Al-2W-0.5Si, will be investigated and correlated with the crack growth behavior at 700°C. The results are reported in the form of the Kitagawa diagram in which the safe and unsafe zones for crack advance and fracture are defined.

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