Advances in Surface Engineering V: Surface Modification and Characterization
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Surface Engineering Committee
Program Organizers: Bharat Jasthi, South Dakota School of Mines & Technology; Arif Mubarok, PPG Industries; Tushar Borkar, Cleveland State University; Rajeev Gupta, North Carolina State University
Thursday 8:30 AM
March 23, 2023
Room: 29D
Location: SDCC
Session Chair: Ganesh Walunj, Buffalo State College
8:30 AM Invited
Dry Electrolyte Polishing of As-printed Additively Manufactured Stainless Steel: Michael Melia1; Erin Karasz1; Kasandra Escarcega-Herrera1; Jason Taylor1; David Saiz1; Michael Heiden1; Jonathan Pegues1; 1Sandia National Laboratories
The as-printed surface of 316L stainless steel parts produced via laser powder bed fusion (L-PBF) is tortuously rough and chemically heterogeneous. Such characteristics lead to variability in the materials surface properties such as susceptibility to local corrosion. Torturous as-printed surfaces have led to many polishing techniques being applied to remove these rough surface features. The present work will show how the as-printed surface of L-PBF 316L is formed, explain what controls the chemical heterogeneities, and explore a process to remove the tortuous surface in dry electrolyte polishing. The presentation will focus on the dry electrolyte polishing as it is a relatively new technique for polishing additively manufactured parts and can produce smooth surfaces with minimal material removal.SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525. SAND2022-8863 A
8:50 AM
Fatigue Behavior of Laser Polished Laser Powder Bed Fused IN718: Identify a Suitable Heat Treatments and Laser Polishing Combination: Seungjong Lee1; Martin Bureš2; Shuai Shao1; Douglas Wells3; Miroslav Zetek2; Nima Shamsaei1; 1Auburn University; 2University of West Bohemia; 3NASA Marshall Space Flight Center
Laser polishing (LP), a remelting-based post surface treatment technique, can significantly reduce surface roughness and near-surface defects of additively manufactured parts. The associated fast solidification, however, introduces inevitable tensile residual stresses detrimental to the fatigue performance of the processed parts, which require further heat treatment (HT) to remove. This study inserts LP after different steps of a full HT schedule (i.e., stress-relief, hot isostatic pressing (HIP), and solution-annealing + aging), examines the resulting fatigue behavior of laser powder bed fused IN718 specimens, and attempts to identify a suitable HT and LP combination. Uniaxial, fully-reversed fatigue tests were conducted in strain-controlled mode. Surface measurements, microstructure characterizations, and porosity measurements were performed for all conditions to explain the differences in fatigue lives. The preliminary results show that performing LP before HIP could eliminate any subsurface defects introduced by LP, restore surface material strength, and is expected to yield the best fatigue resistance.
9:10 AM
A Study of Microstructural Evolution in Peened AISI 304L Stainless Steel: Sesily Stewart1; Indrajit Charit2; Merbin John3; Alessandro Ralls4; Manoranjan Misra4; Pradeep Menezes4; 1University of Idaho; 2University of Idaho ; 3University of Nevada Reno; 4University of Nevada Reno
Dry storage canisters used for spent fuel storage are typically sealed with fusion welding. To improve the longevity of these welds, it is proposed to treat the exposed weld surface with shot peening (SP), laser shock peening (LSP), and ultrasonic impact peening (UIP). Peening has consistently shown improved fatigue and stress corrosion cracking resistance. The objective of this work is to understand the effect SP, LSP, and UIP has on the metallurgical properties of fusion welded AISI 304L SS samples. Scanning electron microscopy and electron backscatter diffraction revealed evidence of grain refinement across the treated surface with UIP showing the greatest amount of deformation. Transmission electron microscopy analysis is performed on different peened samples to examine the extent of severe plastic deformation and amorphization (if any) across the treated surface. This work is supported by the US DOE Nuclear Energy University Program (NEUP), grant DE-NE0008957.
9:30 AM
Effect of Intercritical Annealing Temperature and Sb Micro-addition on the Selective Oxidation of a Fe-6wt.%Mn Alloy: Bita Pourbahari1; Joseph R. McDermid1; 1McMaster University
The effects of annealing parameters and a Sb micro-addition on oxide morphology and selective oxidation kinetics of a Fe-6 wt.% Mn alloy were determined. Increasing the annealing temperature led to coarsening of the surface oxides. Moreover, holding for a longer time at the annealing temperatures resulted in a decrease in bare area or the increase of oxide-covered surface and growth of the oxides. Adding Sb changed the morphology of the oxides from continuous to a granular and lensed shape morphologies, which was attributed to the Sb segregation to the surface during annealing and a decrease in the surface energy. Cross-sectional FIB analysis showed that the Sb addition resulted in a significant reduction of the internal oxidation zone and thickness of the external oxides, which was due to Sb segregation to the external oxide/substrate and internal oxide/substrate interfaces, thereby reducing the inward diffusion of oxygen and outward diffusion of Mn.
9:50 AM
Hot Stamping of Aluminum 6061 Alloys with Volatile Media Injected through Additive Manufactured Die: Lihong Cai1; Meiling Geng1; Ju-Hoon Lee2; Byung-Sun Park2; Sung-Tae Hong1; 1University of Ulsan; 2Dae Sung Company
In the hot stamping process suggested in the present study, the liquid CO2 served simultaneously as a quenching media for a high cooling rate and a lubricant to reduce seizures in stamping. For proper lubricating performance, an additive manufactured die with micro-holes was designed to directly supply the liquid CO2. There are three stages in the hot stamping with the liquid CO2. The aluminum 6061 alloy sheet was heated to solid heat treatment temperature during the heating stage. In the stamping stage, the liquid CO2 was supplied to provide lubrication between the workpiece and the die while the heated sheet was being deformed to the desired shape. Finally, the stamped sheet was quenched by the liquid CO2 and the die at the holding stage. The material property of the hot-stamped aluminum 6061 alloys was analyzed by the Vicker hardness test, and surface roughness test.
10:10 AM Break
10:25 AM
Investigation of Surface Properties of Cemented Steel E16NCD13 after Vibratory Peening: Anindya Das1; Hong-Yan Miao1; Benoît Changeux2; Etienne Martin1; 1Polytechnique Montreal; 2SAFRAN Tech - Materials & Processes Department
Recent developments in the process of vibratory peening, which is a combination of shot peening and vibratory finishing processes, has shown to produce effective residual stresses and better surface finish on the material. The present work attempts to utilise the above benefit on a cemented steel E16NCD13, which finds extensive application in the aerospace industry. Vibratory peening was performed at various Almen intensities and the surface properties are compared with shot peening of same Almen intensity. Vibratory peening was found to be more effective in reducing the surface roughness of the steel than shot peening. Although higher compressive residual stress developed in shot peening, the depth of the residual stresses are higher after vibratory peening along with hardness. Microstructural characterization was performed to explain the above variation and individually assess the surface integrity after both vibratory and shot peening on E16NCD13 steel.
10:45 AM
Laser Induced Micro/Nano Structured Stainless Steel Surfaces for Biological and Food Storage Applications: Gopinath Perumal1; Mark Swayne1; Dermot Brabzon1; 1Dublin City University
The purpose of this work is to investigate the application of laser micro- and nano-machining techniques in the production of modified stainless steel surfaces with regulated wettability and oxide layer composition. We employed a simple one/two-step strategy to build micro, nano, hierarchical patterns, and laser-induced periodic surface structures (LIPPS) on stainless steel. Designs of experiments (Box–Behnken approach), were used to optimise the laser parameters. Developed structures were later characterised for their bio-corrosion properties using electrochemical analysis such as potentio-dynamic polarization, electrical impedance spectroscopy (EIS), and Mott-Schottky (M-S) experiments. X-ray photoelectron spectroscopy (XPS) was used to evaluate the surface composition of the passive layer. Wettability, and surface roughness studies were done to correlate the enhanced anti-bacterial efficacy of laser ablated surfaces. Thus, the higher fidelity approach presented in this work provides a new avenue for the facile design and development of superior surface modification techniques for food storage and bio-applications.
11:05 AM
Mechanical Behavior of AISI 8620 Steel`s Surface Modified through TIG Arcing: Sachin Balbande1; Nilesh Kumar Paraye1; Sourav Das1; 1IIT Roorkee
AISI 8620 is generally low carbon steel which is used in many applications such as bearing, camshaft, fastener, gear and so on. These applications require good surface hardness, toughness and wear resistance. Introducing in situ formation of carbide is one of the ways to improve properties through the tungsten inert gas arcing (TIG) process. Microstructural characterization reveals that the modified surface consists of martensite in lathe form and irregular shapes of precipitates. X-ray diffraction (XRD) shows the presence of the TaC phase formed on a modified surface. Energy dispersive spectroscopy (EDS) mapping shows tantalum and carbide distribution at the precipitate location. The selected area electron diffraction (SAED) pattern confirms that precipitate has a cubic structure. The modified surface has been marked as an increment in hardness and wear as compared to the base metal.
11:25 AM
Nitriding-Assisted Surface Enhancement of Multi-Principal Element Alloys Containing Refractory Metals: Yu-Hsuan Lin1; David Poerschke1; 1University of Minnesota
Multi-principal elements alloys (MPEAs) consisting of refractory metals can retain high yield strength to elevated temperatures, making them attractive for high temperature applications. Surface modification processes can be used to improve their surface hardness, and wear and corrosion resistance. However, there are few studies on nitriding processes for alloys containing refractory metals. This work focuses on understanding the competition for nitrogen reaction between the nitride-forming refractory metals in different MPEA systems, and how it influences the chemistry and the microstructures of the nitrided zones. Refractory alloys comprising single BCC solid solution or dual-phase BCC and ordered B2 phase, and with varying fractions of 3d transition metals were prepared by arc melting, annealing, and then processed by gas nitriding. Characterization of the nitride layer growth, diffusion zone thickness, and internal nitridation provides insight to help navigate the vast design space of MPEAs and develop surface enhancement strategies in the future.
11:45 AM
On Characterization of Microstructure and Surface Attributes in Drilling Processes at High Spatial Resolution: Abhishek Somani1; James Mann2; Srinivasan Chandrasekar1; Kevin Trumble1; 1Purdue Univesity; 2M4 Sciences
Mechanical drilling removes material by large-strain deformation, with various changes resulting to the mechanical state of the surface at the micrometer-scale. Characterizing the surface state at length scales on the order of ~ 10 μm is therefore critical for understanding hole surface integrity. We present results from an experimental study of surface quality attributes in mechanical hole drilling of two commercially important hard alloys – hardened AISI 4140 Steel (~45 HRc ) and ATI-720 superalloy. The surface topography, hardness and microstructure – are characterized using a taper-sectioning technique to access the very near hole-surface region. The surface deformation characteristics are explored at high spatial resolution using optical metallography, nano- and micro- indentation, and optical profilometry. We demonstrate the capability of the taper-sectioning approach, and its use for discriminating both process parameter attributes and different mechanical hole-making processes. Industrial applications and implications for studying performance attributes of drilled holes are discussed.
12:05 PM
Understanding the Tribo-Corrosion Mechanisms of Laser Processed Steel Deposited by High Deposition Rate Cold Spray Additive Manufacturing Process: Alessandro Ralls1; Jacob Frizell1; Pradeep Menezes1; 1University of Nevada, Reno
The utilization of a high-deposition rate cold spraying (HDR-CS) has revolutionized the approach to component repair and protection. However, these coatings suffer from micro-defects due to inadequate particle bonding, thus resulting in premature failure. Especially when subjected to mechanical and chemical environments, their synergism can greatly diminish the lifespans of HDR-CS coatings. To mitigate these defects, we propose the application of post-laser processing to both densify and strengthen their tribo-corrosion performance in chloride-based environments. By correlating the change of microstructural, mechanical, and wettability properties of the HDR-CS coatings to their tribo-corrosion performance, it was found that post-laser processing is a useful method to enhance its surface properties. The critical change in tribo-corrosion mechanisms is further discussed in this work.