Bending fatigue life characterisation of direct metal laser sintering nickel alloy 718

2015 ◽  
Vol 38 (9) ◽  
pp. 1105-1117 ◽  
Author(s):  
O. Scott-Emuakpor ◽  
J. Schwartz ◽  
T. George ◽  
C. Holycross ◽  
C. Cross ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Nickel Alloy ◽  
Laser Sintering ◽  
Alloy 718 ◽  
Direct Metal Laser Sintering ◽  
Bending Fatigue

Fatigue and Strength Studies of Titanium 6Al-4V Fabricated by Direct Metal Laser Sintering

2015 ◽  
Author(s):  
Onome Scott-Emuakpor ◽  
Casey Holycross ◽  
Tommy George ◽  
Kevin Knapp ◽  
Jeffery Bruns
Keyword(s):  
Fatigue Life ◽  
Additive Manufacturing ◽  
Manufacturing Process ◽  
Fuel Efficiency ◽  
Engine Performance ◽  
Laser Sintering ◽  
Direct Metal Laser Sintering ◽  
Turbine Engine ◽  
Bending Fatigue ◽  
Cold Rolled

Vibratory bending fatigue life behavior of Titanium (Ti) 6Al-4V plate specimens has been assessed. The plates were manufactured via direct metal laser sintering (DMLS), which is a powder bed, laser deposition additive manufacturing process. Motivation for this work is based on unprecedented performance demands for sixth generation gas turbine engine technology. For example, the inclusion of a third stream flow for improving engine performance may add complexity and weight that could offset anticipated thrust and fuel efficiency gains. Therefore, complex, lightweight components with improved functionalities are desired. Novel component design concepts have been cost, schedule, and feasibility limited when using conventional manufacturing methods. Additive manufacturing, however, can extend the thresholds of component concepts. Though additive manufacturing can be a promising addition to the turbine engine community, the manufacturing process controls required to achieve consistency in material properties have not been fully identified. The work presented in this manuscript investigates variability in vibration-based bending fatigue life of DMLS Ti 6Al-4V compared to cold-rolled Ti 6Al-4V. Results show discrepancies between the fatigue life variation of DMLS and cold-rolled data. Along with the support of fusion and post-fusion process parameters, the fatigue results are also supported by tensile property characterization, fractography, and microscopy.

Fatigue and Strength Studies of Titanium 6Al–4V Fabricated by Direct Metal Laser Sintering

2015 ◽  
Vol 138 (2) ◽  
Author(s):  
Onome Scott-Emuakpor ◽  
Casey Holycross ◽  
Tommy George ◽  
Kevin Knapp ◽  
Joseph Beck
Keyword(s):  
Fatigue Behavior ◽  
Laser Sintering ◽  
Direct Metal Laser Sintering ◽  
Turbine Engine ◽  
Powder Bed ◽  
Bending Fatigue ◽  
Microstructure Characteristics ◽  
Sixth Generation ◽  
Cold Rolled ◽  
Process Controls

Vibratory bending fatigue behavior of titanium 6Al–4V plate specimens manufactured via direct metal laser sintering (DMLS), powder bed fusion additive manufacturing (AM), is assessed. Motivation for the work is based on unprecedented performance demands for sixth-generation gas turbine engine technology that requires complex, lightweight components. Due to cost, schedule, and feasibility limitations associated with conventional manufacturing, AM aims to address ubiquitous component concepts. Though AM has promise in the engine community, process controls necessary for consistent material properties remain an enigma. The following manuscript compares variability of DMLS fatigue and strength to cold-rolled data. Results show discrepancies between DMLS and cold-rolled for fatigue and microstructure characteristics.

High Cycle Fatigue Life of Ti6Al4V Alloy Produced by Direct Metal Laser Sintering

2016 ◽  
Vol 258 ◽  
pp. 522-525 ◽  
Author(s):  
Radomila Konečná ◽  
Gianni Nicoletto ◽  
Adrián Bača ◽  
Ludvík Kunz
Keyword(s):  
Fatigue Life ◽  
High Cycle Fatigue ◽  
Fatigue Testing ◽  
Fatigue Behavior ◽  
Fatigue Crack Initiation ◽  
Laser Sintering ◽  
Ti6al4v Alloy ◽  
Cycle Fatigue ◽  
Direct Metal Laser Sintering ◽  
Stress Relieving

High cycle fatigue life of Ti6Al4V alloy specimens manufactured by Direct Metal Laser Sintering (DMLS) was experimentally determined. The DMLS fabrication process was characterized by a 400 W laser power and 50 μm layer melted thickness. Post-fabrication heat treatment consisted in stress relieving for 3 h at 720 °C in vacuum with subsequent cooling in argon atmosphere. Fatigue testing of specimens oriented in three different directions with respect to the material build direction was performed with the aim to examine the influence of the layered microstructure on the fatigue behavior. Results of measurement of surface roughness, metallographic examinations of the layered material and fractographic investigation of the fatigue fracture surfaces were employed in the discussion of fatigue crack initiation in DMLS fabricated Ti6Al4V alloy.

Experimental Study of Direct Metal Laser Sintering: High Cycle Fatigue Life and Process Parameters

2020 ◽  
Author(s):  
Riley Seyffert ◽  
Sudhir Kaul
Keyword(s):  
Fatigue Life ◽  
Layer Thickness ◽  
Process Parameters ◽  
High Cycle Fatigue ◽  
Laser Sintering ◽  
Bending Test ◽  
Cycle Fatigue ◽  
Direct Metal Laser Sintering ◽  
Build Time ◽  
Scan Speed

Abstract Direct Metal Laser Sintering (DMLS) is a relatively new manufacturing process in additive manufacturing (AM) that fuses powdered metal by using a high-powered laser. Although this process allows manufacturing prototypes without requiring specific tooling, it is challenging to use this process for manufacturing high volume production parts since complex shapes can take a significant amount of build time. Furthermore, manufactured parts also need some amount of post-processing to remove the support material that may be required due to the layer-by-layer build process. This study investigates three process parameters that could be optimized to substantially reduce production time. These three parameters are as follows: build layer thickness, laser scan speed, and laser hatch distance. In order to evaluate the influence of these parameters, manufactured parts made of AISI 316L Stainless Steel are tested for fatigue life and static strength. A three-point bending test is used as per ASTM E466. While none of the three parameters is seen to significantly influence ultimate tensile strength, results indicate that build layer thickness is a significant process parameter that directly affects fatigue life. Furthermore, the interaction between build layer thickness and laser scan speed is found to be statistically significant for high cycle fatigue. However, laser scan speed and laser hatch distance are seen to be statistically insignificant for fatigue life. The initial results of this study indicate that process parameters of DMLS need to be selected judiciously in order to minimize build time while maintaining structural integrity.

Sign in / Sign up

Export Citation Format

Share Document