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Technical Paper

Selective Laser Melting of Copper by 200 W CO2 Laser

2016-04-05
2016-01-0333
Due to its unique physical properties (high thermal and electric conductivity) copper is one of the most interesting materials in point of view of additive manufacturing in particular of Selective Laser Melting (SLM). But because of the low laser radiation absorption, low melting point and high thermal conductivity it is difficult to fabricate of copper components without pores. ...Results of many research have been shown that for successful Selective Laser Melting of copper powder is needed high laser power (more than 300 W) and high laser scanning speed (more than 600 mm/s). ...Results of many research have been shown that for successful Selective Laser Melting of copper powder is needed high laser power (more than 300 W) and high laser scanning speed (more than 600 mm/s). However now most SLM machines are equipped with laser plants with output power up to 200 W.In this research, SLM machine with 200 W maximum power CO2 laser has been used.
Technical Paper

Method of Production of Composite Powder Cu-Ni Suitable for Use in Selective Laser Melting

2016-09-27
2016-01-2121
The possibility of using of obtained composite powder in selective laser melting (SLM) was evaluated. It is assumed that the structure of the obtained composite material (SLM) will have inclusions of nickel and continuous chain of copper. ...It is assumed that the structure of the obtained composite material (SLM) will have inclusions of nickel and continuous chain of copper. This structure will have high mechanical properties and high electrical conductivity.
Technical Paper

Method of Producing Composite Powder EP648-Al2O3 for Selective Laser Melting Usage

2016-09-27
2016-01-2117
This method is based on modification of the metal micropowders surface by the second phase in a planetary mixer (mechanochemical synthesis).The obtained composite micropowders are compared with powders which are recommended for selective laser melting usage (produced by MTT Technology). The equipment used in the research: planetary mixer, scanning electron microscopy (SEM), optical granulomorphometer Occio 500nano.
Technical Paper

Effect of Very High Travel Speeds on Melting Efficiency in Laser Beam Welding

1999-03-01
1999-01-0996
Calorimetric measurements of the net heat input to the workpiece have been made to determine the effect of very high travel speeds on laser weld melting efficiency. Very high welding speeds are required in welding applications such as automotive where lasers are now applied extensively. ...Travel speeds as fast as 530 mm/s for continuous wave CO2 laser welding on 304 stainless steel have been examined in this study. Melting efficiency indicates what fraction of the laser power absorbed is used to produce melting rather than undesirable base metal heating. ...Melting efficiency indicates what fraction of the laser power absorbed is used to produce melting rather than undesirable base metal heating. It was found that melting efficiency initially increased then slowly decreased as fusion zone dimensions changed.
Technical Paper

Re-Engineering, Austempering, and Selective Laser Hardening of a 4340 Latch Body used in the Cargo Hook of a CH-47 Military Helicopter

2007-09-17
2007-01-3809
The application of laser technology for surface hardening of the austempered latch body is reported. Mechanical testing of austempered 4340 steel, microstructural examination, characterization of the laser and induction hardened layers, and preliminary testing to evaluate the integrity of the hardened layers is presented. ...Mechanical testing of austempered 4340 steel, microstructural examination, characterization of the laser and induction hardened layers, and preliminary testing to evaluate the integrity of the hardened layers is presented.
Technical Paper

Laser Material Processing

1985-02-01
850406
An overview of laser processing techniques was presented to review the advantages and disadvantages of these emerging techniques. ...The importance of a manufacturing feasibility study, after the initial technical feasibility study and cost justification, was highlighted in the implementation of a particular laser processing application. Some examples of both types of feasibility studies were presented. ...Lastly, a projected future of laser processing was discussed to assess the direction in which this technology is heading.
Technical Paper

Thermal Validation Study of AdBlue® Melting for Off Highway Vehicles

2022-03-29
2022-01-0560
Selective Catalytic Reduction (SCR) is a process where one injects an aqueous solution of urea into a diesel exhaust system in order to reduce NOx emissions. ...In this article, we investigate whether a CFD (Computational Fluid Dynamics) based methodology can accurately evaluate time required in melting AdBlue® for a given DEF Tank and heater coil design for a production vehicle as per standard testing procedure.
Technical Paper

Study of Surface Integrity and Effect of Laser Peening on Maraging Steel Produced by Lasercusing Technique

2018-07-09
2018-28-0094
In additive manufacturing, lasercusing is the selective laser melting technique. Finely pulverized metal is melted using a high-energy fibre laser, by Island principle strategy produces mechanically and thermally stable metallic components with reduced thermal gradients, stresses & at high precision. ...Finely pulverized metal is melted using a high-energy fibre laser, by Island principle strategy produces mechanically and thermally stable metallic components with reduced thermal gradients, stresses & at high precision. ...Current research attempts to analyze the effect of laser shock peening on lasercused material. Surface roughness of the material was found to be increased by 8%, due to effect of laser shock pulse & ablative nature.
Standard

Ice Melting Test Method for Runways and Taxiways Deicing/Anti-icing Chemicals

2017-02-21
CURRENT
AIR6170A
This test method provides stakeholders (runway deicing chemical manufacturers, users, regulators, and airport authorities) with relative ice melting capacity of runway deicing chemicals, by measuring the amount of ice melted as a function of time. ...This test method does not quantitatively measure the theoretical or extended time ice melting capability of ready-to-use runway deicing/anti-icing chemicals in liquid or solid form.
Standard

Ice Melting Test Method for AMS1431 and AMS1435 Runway Deicing/Anti-Icing Products

2021-10-28
CURRENT
AS6170
This test method provides stakeholders (runway deicing/anti-icing product manufacturers, users, regulators, and airport authorities) with relative ice melting capacity of runway deicing/anti-icing products, by measuring the amount of ice melted as a function of time. ...This test method does not quantitatively measure the theoretical or extended time ice melting capability of ready-to-use runway deicing/anti-icing product in liquid or solid form.
Book

Laser Diagnostics and Optical Measurement Techniques in Internal Combustion Engines

2012-07-30
The increasing concern about CO2 emissions and energy prices has led to new CO2 emission and fuel economy legislation being introduced in world regions served by the automotive industry. In response, automotive manufacturers and Tier-1 suppliers are developing a new generation of internal combustion (IC) engines with ultra-low emissions and high fuel efficiency. To further this development, a better understanding is needed of the combustion and pollutant formation processes in IC engines. As efficiency and emission abatement processes have reached points of diminishing returns, there is more of a need to make measurements inside the combustion chamber, where the combustion and pollutant formation processes take place. However, there is currently no good overview of how to make these measurements.
Technical Paper

Laser Forming of Aerospace Alloys

2001-09-10
2001-01-2610
Recently, it has been shown that much greater controllability can be introduced by replacing the thermal source with a laser. This yields a process with strong potential for application in aerospace, including the rapid manufacture of prototypes and the adjustment of misaligned components. ...This paper briefly reviews the mechanisms involved in laser forming and then summarises experimental work carried out on aluminium alloys and titanium alloys that led to the development of a prototype system for the forming of 2-D sheet materials. ...Future work in a new collaborative programme to develop 3-D laser forming is summarised.
Standard

Laser Peening

2020-05-19
CURRENT
AMS2546A
This specification covers the requirements for computer-controlled laser peening of metal part surfaces to induce residual compressive stresses at and beneath the surface.
Technical Paper

Selective Strippability

1994-03-01
941240
The concept of having an intermediate coat between the primer and topcoat in an airliner exterior paint scheme has enabled the selective removal of the topcoat by chemical stripping leaving the primer unaffected. This principle has opened up the possibility for chemical stripping of a paint scheme using less aggressive, more environmentally friendly chemical strippers and the possibility of being able to chemically strip paint from composite parts.
Journal Article

Thermal Analysis of Urea Tank Solution Warm Up for Selective Catalytic Reduction (SCR)

2009-04-20
2009-01-0971
Due to the stringent requirements to reduce the tail pipe emissions of NOx, Selective Catalytic Reduction (SCR) systems are used to remove NOx using ammonia. When a urea solution is injected into the exhaust system, urea will undergo hydrolysis and decomposition reaction that produces ammonia. ...At the start up of a vehicle under such low ambient temperatures, a heating system is used to provide the heat required for melting the frozen urea. Therefore, there will be a time lag between the vehicle start up and the availability of urea solution to the SCR system.
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