Michael Ghil, Mickaël D. Chekroun and Dmitri Kondrashov Dept. of Atmospheric & Oceanic Sciences and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 603 Charles E. Young Dr., East, 3845 Slichter Hall Los Angeles, CA 90095-1567 Ghil phone: (310) 825-1038 fax: (310) 206-5219 email:[email protected] Chekroun phone: (310) 825-1038 fax: (310) 206-5219 email:...

We report on the effect of femtosecond-laser-induced periodic surface structures (LIPSS) on the tribological properties of stainless steel. Uniform periodic nanostructures were produced on AISI 304L (American Iron and Steel Institute steel grade) steel surfaces using an 800-nm femtosecond laser. The spatial periods of LIPSS measured by field emission scanning electron microscopy ranged from 530...

In this research work a series of tests were conducted in order to determine flank wear and cutting force FY on hard AISI 440 C martensitic stainless steel and SCM 440 alloy steels. The operating parameters are cutting speed, feed rate and a constant depth of cut to investigate the flank wear and cutting force. No cutting fluid was used during the turning process. The cutting tool used was CBN ...

The purpose of this research paper is to study the tool wear and surface roughness of AISI 8620 material using coated ceramic tool by turning process. Ceramic cutting tools have outstanding material hardness, resistance to high temperatures, wear resistance, chemical stability and hot hardness. Ceramic tool with Al2O3 + TiC (golden) coating was used to investigate the surface roughness and tool...

AISI 4140 powder was directly deposited on AISI 4140 wrought substrate using laser engineered net shaping (LENS) to investigate the compatibility of a LENS-deposited part with the substrate. Tensile testing at room temperature was performed to evaluate the interface bond performance and fracture behavior of the test specimens. All the samples failed within the as-deposited zone, indicating that...

In the present work CO2 continuous laser welding process was successfully applied and optimized for joining a dissimilar AISI 316 stainless steel and AISI 1009 low carbon steel plates. Laser power, welding speed, and defocusing distance combinations were carefully selected with the objective of producing welded joint with complete penetration, minimum fusion zone size and acceptable welding pro...

In this study, 3-D finite element modeling of precision hard turning has been used to investigate the effects of cutting edge microgeometry on tool forces, temperatures and stresses in machining of AISI H13 steel using polycrystalline cubic boron nitrite (PCBN) inserts with two distinct edge preparations. Hard turning experiments were conducted to investigate the effects of cutting edge geometr...

A simple and effective method without vacuum to control the wetting properties of AISI 316L stainless steel using femtosecond laser pulses at high repetition rate has been developed. Both hydrophilic and hydrophobic surfaces were formed by creating micro-conical structures on the surface with femtosecond laser irradiation in air. The scan speed was found to be an effective parameter in controll...

This paper focuses on understanding the influence of laser milling process parameters on the final geometrical and surface quality of micro-channel features fabricated on AISI H13 steel. Optimal selection of process parameters is highly critical for successful material removal and high dimensional and surface quality for micro-sized die/mold applications. A set of designed experiments is carrie...

Fatigue behavior of case hardened parts depend to a great extent on the type of residual stresses developed in the components. Topography and metallurgical effects were the two elements which contribute much to surface integrity. Micro hardness of the gas carburized (EN 33 and EN 36) and Induction hardened (AISI 1040 and AISI 6150) specimens obtained during experiments, showed that there was gr...