Grade Stainless Steel Research Articles

Electrochemical behavior and microstructure of diffusion welding of zirconium alloy and super duplex stainless steel

In this study, the effect of welding temperature on interface microstructure, mechanical properties, and electrochemical behavior of diffusion welded joints (DWJs) of zirconium alloy (ZrA, Zr702 grade) and super duplex stainless steel (2205 duplex stainless steel grade) were investigated. Alloys were welded in a vacuum atmosphere at four different temperatures (800, 850, 900, and 925 °C) for 75min under 4MPa compressive pressure. The optical, scanning electron microscopy, electron probe micro-analyzer, and X-ray diffraction techniques were used to characterize the interfacial microstructure of the DWJs. Layers of intermetallics were formed along the welded interface at 850 °C and above welding temperatures. At 850 °C, a single reaction layer (phase mixture of ZrFe2+ZrCr2) was observed; however, bilayers (ZrFe2+ZrCr2 and Fe2Zr+FeZr3 phase mixtures), and triple layers (ZrFe2+ZrCr2, Fe2Zr+FeZr3, and β-Zr+FeZr3 phase mixtures) were observed at the welded interface of the joints processed at 900 and 925 °C, respectively. Width of the reaction layer (phase mixtures) increases with an increase in the welding temperature. The DWJs processed at 900 °C reach the maximum joint strength of ~312MPa along with ~6.4% ductility. For corrosion analysis, studies of the base alloys and DWJs in 0.1mol/L HCl and 0.1mol/L NaOH solutions separately using electrochemical techniques, such as open circuit potential, electrochemical impedance spectroscopy, and potentiodynamic polarization were undertaken.

Corrosion Ferritic Stainless Steel in a Simulated Hydrothermal Liquefaction Bioconversion Aqueous Solution: Effect of Surface Cr Content

Abstract The objective of this study was to determine the effect of surface Cr content on the corrosion of ferritic stainless steels in hot pressurized alkaline water (310 °C at 10 MPa) simulating a hydrothermal liquefaction bioconversion medium. Two methods to increase the Cr surface content were investigated: (i) selecting commercial grades of ferritic stainless steel with an increasing Cr content and (ii) applying a Cr coating (chromizing) to a low-Cr (Type 409) ferritic stainless steel. The observed parabolic-like corrosion kinetics were analyzed and discussed in terms of the structure and composition of the double layered oxide films that formed. The (surface) Cr content is a critical factor affecting corrosion. Corrosion was reduced by 66% (after 20 days exposure) when increasing the Cr content from 9 wt.% (P91) to 21 wt.% (SS443) in the commercial grades of ferritic stainless steel. Moreover, corrosion was reduced by 84% (after 20 days exposure) by chromizing the surface of a low-Cr (Type 409) ferritic stainless steel. Improved corrosion protection was attributed to increased Cr incorporation into the inner (barrier) Fe(Fe1-nCrn)2O4 layer, with the formation of a Cr2O3 layer (resulting from chromizing) being most beneficial.

Effect of Oxide’s Thermophysical Properties on 2205 Duplex Stainless Steels ATIG Welds

Duplex stainless-steel grade 2205 (2205 DSS) is the most widely used of the current duplex materials. The duplex steel alloy is characterized by high strength and high corrosion resistance through enhancing nitrogen and molybdenum contents. The activated tungsten inert gas (ATIG) welding technique uses the same equipment as tungsten inert gas (TIG), but prior to the welding operation, a thin layer of flux is deposited. Activation fluxes are known to influence the shape and energy characteristics of the arc. They promote the change in shapes and dimensions of the welds, namely, increasing the depth and narrowing the weld width. This work is dedicated to investigate the influence of the thermophysical properties of individual metal oxide fluxes on 2205 DSS welding morphology. It helps also to identify the recommended flux properties in order to perform full penetrated ATIG welds. Thirteen kinds of oxides (SiO2, TiO2, Fe2O3, Cr2O3, ZnO, Mn2O3, V2O5, MoO3, Co3O4, SrO, ZrO2, CaO, and MgO) have been tested and three current intensity levels (120, 150 and 180 A) have been considered. The results showed that the main input factors affecting the weld depth (D) were the welding current intensity with a contribution of up to 53.36%, followed by the oxides enthalpy energy with 15.05% and then by the difference between the oxides and the base metal of 2205 DSS (BM 2205 DSS) melting points with a contribution of 9.71% of the data variance. The conditions on individual oxides’ thermophysical properties to achieve full penetrated weld beads have been also revealed.

Stainless steel I-section beams at elevated temperatures: Lateral–torsional buckling behaviour and design

In this paper, a comprehensive investigation into the structural response and design of stainless steel I-section beams susceptible to lateral–torsional buckling (LTB) at elevated temperatures is carried out. A very large number of stainless steel I-section beams are considered, taking into account various cross-section geometries, beam slendernesses and different stainless steel grades and elevated temperature levels. Extensive structural performance data on the behaviour of stainless steel I-section beams are generated through nonlinear shell finite element modelling. Assessment of the existing LTB design rules for stainless steel I-section beams at elevated temperatures provided in the current version of the European structural steel fire design standard EN 1993-1-2 and its upcoming version prEN 1993-1-2 is presented. New LTB design rules based upon an Ayrton-Perry equation that is able to provide a consistent mechanical appraisal of the LTB behaviour of stainless steel I-section beams in fire are proposed. The accuracy and safety of the proposed new LTB design rules for stainless steel I-section beams are comprehensively verified. It is also shown that the proposed LTB design equations in this paper lead to a considerably higher level of consistency and reliability for the LTB design of stainless steel I-section beams in fire relative to the LTB assessment rules provided in EN 1993-1-2 and prEN 1993-1-2.

Corrosion Properties of Weld Metal in 304 Stainless Steel for Food Grade Using GTAW with Various Types of Backing Gas

This study investigated the impact from nitrogen content in backing gases on the microstructure and corrosion resistance of food grade stainless steel weld metal. Three types of backing gases were employed: 100%Ar, 85%Ar+15%N2, and 100%N2. Statistical analysis using ANOVA revealed a significant effect from nitrogen content on the ferrite phase fraction within the weld metal microstructures (p-value = 3.5E-05), indicating a reduction in the ferrite phase with increasing nitrogen content. Moreover, increasing nitrogen content positively shifted the pitting corrosion potential, indicating enhanced corrosion resistance. Optical microscopy confirmed lower pit density in samples with nitrogen backing gas as compared with samples with argon backing gas. These findings underscore the crucial role of nitrogen content in backing gases at influencing microstructure and corrosion resistance in stainless steel weld metal, with higher nitrogen levels correlated with improved corrosion resistance.

Sintering behaviours of different ladle filler sands with high-chromium stainless steel

In order to investigate the sintering behaviours of different types of filler sands (chromite-based, zircon-based, and silica-based) with high-chromium stainless steel grades ( w[Cr] = 11.70% and 16.26%), laboratory experiments were carried out at 1600°C in an inert atmosphere. It is found that the high content of Cr in stainless steel promotes the formation of Cr2O3 in the liquid phase of these sintered filler sands, thereby significantly affecting the sintering of the filler sands. Compared with the elements of Mn and Al in conventional steel grades, the Cr element in stainless steel shows a different impact on the sintering of filler sands. The sintering of chromite-based sands is restricted by the rise of Cr content in stainless steel, whereas the dissolved Cr in the steels enhances the sintering of zircon-based and silica-based filler sands. Chromite-based filler sands are recommended for stainless steel. Because the melting point of the liquid phase is significantly influenced by the content of (Cr2O3 + Al2O3), the contents of Al2O3 and Cr2O3 in chromite-based sands should be accordingly adjusted for stainless steel.

Mechanical and failure behaviors of adhesively bonded dissimilar materials joints incorporating bio-inspired morphological irregularities

Adhesive dissimilar material joints between stainless steel grade 316L and polyethylene terephthalate glycol (PETG) plastic were examined, in which irregular interface morphologies inspired by natural sutures were incorporated. The joint interfaces exhibited various teeth-like, non-repetitive zigzag patterns based on a pseudo-randomization method and sutural interdigitation index. Effects of their irregularities on mechanical and failure characteristics of adhesive butt joints were studied by means of experiments and FE simulations. The cohesive zone model, Drucker-Prager plasticity model and ductile failure criterion were applied for the interface and PETG, respectively. Predicted load-displacement curves of joints with different teeth profiles were well validated. The degree of irregularity became higher to 20 %, 40 %, and 60 %, the joint strengths decreased by 1.47 %, 5.39 %, and 11.95 %, while the total energies to failure increased by 110.74 %, 129.33 %, and 161.23 %, accordingly. More inhomogeneous morphologies led to earlier local damage initiation, but enhanced damage evolution range by impeding abrupt joint separation. Smaller teeth angles provided higher joint strength, whereas significant declines of bonding strength were observed by too acute teeth angle due to excessive stress localization and resulting teeth breakage. The teeth angle of 45° enabled the superior joint performance owing to a proper combination of interlocking and large adhesive force under shear stress state. Finally, a key insight for designing an optimal dissimilar joint with morphological irregularities was provided.

Microstructure and Mechanical Properties of Bimetallic Structure Fabricated through Wire Plus Arc Additive Manufacturing

This study investigates the fabrication and mechanical assessment of bimetallic structure (BMS) wall using wire plus arc additive manufacturing (WAAM) technology, employing stainless steel (SS) 304 and SS 308L SS filler wire. The usage of BMS is promoted due to the limitation faced during dissimilar welding of the SS grades. The high or improper melting of the interface will lead to elemental segregation, leading to structural failure. Producing seamless BMS plates will be an ideal replacement for dissimilarly welded joints. Notably, 308L SS demonstrates superior mechanical properties compared to 304 SS, exhibiting impressive tensile strength (TS) and exceptional ductility. BMS, constructed with 308L filler wire, closely matches these better mechanical attributes, making it an attractive choice for applications prioritizing mechanical performance. Furthermore, when compared to WAAM‐processed SS 304, BMS consistently outperforms in terms of TS while retaining remarkable ductility. This is due to the variation in the microstructure caused by complex thermal cycles. Hence, this research provides valuable insights into manufacturing and characterization of BMS, emphasizing the potential of WAAM‐processed BMS (SS 304/SS 308L) in engineering applications demanding superior mechanical properties while replacing dissimilar joints in the fields of aerospace, aviation, automobile, and power generation industries.

Phase quantification in a duplex stainless steel welds using NDT techniques

ABSTRACT Duplex stainless steels are composed of ferrite and austenite in equal volume fractions of these phases, which provides an excellent combination of mechanical properties and corrosion resistance, especially when compared with conventional stainless steel grades. When these steels are welded, there are significant changes in the austenite-to-ferrite ratio therefore in their final properties. Nowadays, the ferritoscope is the unique non-destructive technique used to quantify these two phases content in situ. This tester instrument is limited to the evaluation of large areas, is not suitable for the heat affected zone and is also very sensitive to the surface finish, being considered an intermediate precision technique. So, it is necessary to develop more reliable field techniques. In this research, thermoelectric power measurements and induced current techniques are proposed to evaluate the phase quantification in S32205 welds. According to the results, both techniques are reliable and highly sensitive to phase changes in the weld bead, heat affected zone and base metal. For the thermoelectric power technique, a probe with nickel tip should be used to obtain the highest sensitivity and for the induced current technique, a probe type-pencil with a central frequency of 6 MHz should be used.

Integrating double-labeling HCR-FISH into a multidisciplinary pipeline for biofouling assessment on austenitic stainless steel in brackish seawater circuit

This study modified and integrated a bioimaging method of hybridization chain reaction fluorescence in situ hybridization (HCR-FISH) into a pipeline for assessing biofouling on stainless steel (SS). A modified protocol of double-labeling HCR-FISH was directly applied to two surface types of SS grade EN 1.4404 to detect localized bacteria and sulfate-reducing bacteria (SRB) by targeting bacterial 16 S rRNA genes and dissimilatory sulfite reductase (dsrB) genes, respectively. The protocol was first validated using microbial pure cultures and materials before being integrated into a biofouling assessment pipeline of SS in a laboratory-scale brackish water circuit, incorporating electrochemical, surface, and molecular biology characterization analyses. The double-labeling HCR-FISH improved bioimaging of surface biofilm morphology and microbial distribution, surpassing monochrome staining methods. This method was compatible and complemented other microscopy techniques and molecular biological analyses, providing additional insights into the biofilms and deposits on the alloy surfaces. The implemented assessment pipeline for biofouling determination frequently detected the ennoblement phenomenon in the evolution of marine biofilm on SS surfaces. However, within the experimental timeframe, microbial activities in the brackish seawater circuit did not flourish significantly, resulting in minimal impact on the steel material. Additionally, surface type and roughness may correlate with microbial adhesion, biofilm growth, and the deformation of passivation layers in SS. Despite abundant sessile bacteria, particularly opportunistic microorganisms, on the steel surfaces, no direct correlations with biodeterioration phenomena or influences of surface roughness of an alloy and the presence of biofilm were conclusively established.

VALIDATION AND PARAMETRIC STUDY OF LEAN DUPLEX STAINLESS STEEL HOLLOW SECTION STUB COLUMNS BY FINITE ELEMENT ANALYSIS

In this research, a parametric study was conducted on square hollow sections (SHS) and rectangular hollow sections (RHS) columns made of a lean duplex stainless steel (LDSS) grade, namely EN 1.4162. The aim was to determine structural response data due to variations of different design parameters, which is vital in designing structural members. Finite element modeling was utilized for this and the validity of the models was confirmed by comparing them with existing experimental test data. Thickness, corner radius, load eccentricity and slenderness ratio were taken as the varying parameters to study. A total of 32 columns were modeled to study with five variations for each parameter, making a total of 160 variations. For each variation, the ultimate load and the corresponding end shortening were recorded. Each parameter has some effects on ultimate load or end shortening or both except corner radius, which has no significant effect. To visualize the effect of a parameter, a trend line equation was developed by plotting the average result of all column models for each variation of that particular parameter. A linear increase in ultimate load and end shortening can be observed with an increase in column thickness, while opposite trends were witnessed with load eccentricity. Though a linear rise in end shortening was caused by the slenderness ratio, no significant change was seen in the ultimate load of the columns. The mathematical equations presented can be employed to forecast the maximum load-bearing capacity and the associated amount of end shortening when designing structural hollow sections made of LDSS.

Experimental Study on the Ignition Behavior of Wildland Fuels Ignited by Heated Stainless-Steel Particles

ABSTRACT Hot metal particles from activities like machining, grinding, and welding are significant ignition sources for wildland fuels. Thus, this study examines the effects of stainless-steel particle geometries and wildland fuel beds on wildfire ignition behavior. To this purpose, experiments have been conducted to investigate the impact of particle type, composition, diameter, number, and wildland fuel bed species on ignition behavior. Three common California wildland grass fuel species were studied: Bromus (Bromus diandrus), Tall Wheatgrass (Thinopyrum ponticum), and Avena Wildoats (Avena fatua). Various stainless-steel grades were tested as ignition particles. The findings from this study support prior research and indicate that increasing the quantity and diameter of ignition particles reduces ignition temperature and affects the type of ignition (flaming, smoldering, or none). Moreover, results from this study showed that decreasing the carbon content in stainless steel may lower the temperature required to reach wildland fuel ignition. In addition, wildland fuel species influenced ignition type and temperature. For instance, Bromus fuels had the lowest flaming ignition temperature at 320°C whereas Tall Wheatgrass and Avena ignited at 400°C and 380°C, respectively. Flaming ignition was primarily observed in Bromus fuels, while Avena and Tall Wheatgrass primarily supported smoldering ignition. This work asserts that species-specific fuel morphology, chemical, and thermal properties affect the flammability of grassy fuels when these are ignited by metal particles and observes that in addition to particle geometry, the chemical properties of ignition particles, such as carbon content, may also lay a key role in shapping ignition behavior.

Environmentally Assisted Cracking of Duplex and Lean Duplex Stainless Steel Reinforcements in Alkaline Medium Contaminated with Chlorides

Herein, the corrosion performance of different stainless steel (SS) reinforcing bar grades in alkaline solution is presented, including UNS S32205 duplex stainless steel (DSS), UNS S32304 and UNS S32001 lean DDS (LDSS). The electrochemical dissolution kinetics were studied by potentiodynamic polarization and the Tafel slope method. The environmentally assisted cracking (EAC) mechanisms of the different SS grades in the presence of Cl− were revealed with the slow strain rate test (SSRT). The higher activation of the anodic branch and the loss of toughness were related to the austenite-to-ferrite phase ratio. UNS S32205 DSS presented the slowest anodic dissolution kinetics, mainly due to the higher austenite content compared to the other LDSS; however, it suffered a more severe EAC than the UNS S32304 LDSS. In the case of UNS S32001 LDSS, even while having the lowest Ni content (i.e., large ferrite α-phase ratio), it experienced the least decrease in elongation as well as low anodic dissolution kinetics for Cl− contents up to 8 wt.%, where the Cl− threshold was reached.

Laser Powder Bed Fusion and Heat Treatment of the Martensitic Age‐Hardenable Steel (1.2709)

The primary objective of this study is to clarify the fundamental question of whether, in principle, it is possible to dispense with a prior solution annealing process in favor of a direct aging heat treatment for specimens of maraging stainless steel grade X3NiCoMoTi18‐9‐5 (1.2709) produced by laser powder bed fusion (LPBF). The waiver of a solution annealing process would significantly increase the process efficiency and thus support a sustainable and resource‐friendly production of such components. Therefore, the hardness, microstructure, and the present phases of specimens in as‐built + aged condition (AB + A) and solution‐annealed + aged (SOL + A) are examined during this study. Initially, an extended parameter study is performed using a Renishaw AM 250 LPBF system equipped with a pulsed mode laser system to achieve the highest possible apparent density. As test specimens, small cubes are produced for parameter study and are analyzed for porosity by means of optical microscopy. To investigate the relationship between microstructure and hardness in different material states, one series of specimens is aged directly after LPBF processing in the as‐built state (AB + A). For comparison, the other series was solution annealed at 820 °C for 60 min, quenched in water and then aged (SOL + A). A maximum hardness value of 614 HV1.0 is achieved for specimen aged at 490 °C for 120 min in as built condition (AB + A), while 624 HV1.0 was measured for specimen aged at 490 °C for 180 min in conventionally solution annealed + aged (SOL + A) condition. Significant austenite reversion is not observed at aging temperature of 490 °C in both cases. Aging of specimens at temperatures of 540 and 600 °C resulted in reduction of specimen hardness due to higher percentage of austenite reversion. No significant difference between the hardness values of AB + A and SOL + A specimens is observed. It can therefore be concluded that, in principle, conventional solution annealing and ageing can be dispensed with in favor of direct aging. However, as the results are based on small sized specimens, further investigations into the scalability are needed.

Thin Layers of Cerium Oxynitride Deposited via RF Sputtering.

Thin films of transition metal oxides and oxynitrides have proven highly effective in protecting stainless steels against corrosion in both chemically aggressive environments and biological fluids. In the present work, cerium zirconium oxynitride thin films were deposited to enhance the corrosion resistance of surgical-grade stainless steel to be used in osteosynthesis processes. Two techniques were employed: co-sputtering and radiofrequency (RF) sputtering, and the morphology and corrosion efficiency of the coatings deposited by each technique were evaluated. X-ray diffraction, X-ray photoelectron spectroscopy and field emission transmission electron microscopy were used to characterize the morphological and chemical structure, respectively. Additionally, the corrosion resistance of the oxynitride-coated surgical grade stainless steel system (ZrCeOxNy-AISI 316L) was assessed using Hank's solution as the corrosive electrolyte, to determine its resistance to corrosion in biological media. The results show that ZrCeOxNy coatings increase the corrosion resistance of surgical grade stainless steel by two orders of magnitude and that the Ce(III)/Ce(IV) equilibrium decreases the corrosion rate, thereby increasing the durability of the steel in a biological environment. The results show that Ce coatings increase the corrosion resistance of surgical grade stainless steel by two orders of magnitude and that the Ce(III)/Ce(IV) equilibrium decreases the corrosion rate, thereby increasing the durability of the steel in a biological environment.

Study and Application on the Electromagnetic Stainless Steel: Microstructure, Tensile Mechanical Behavior, and Magnetic Properties.

Stainless steel grade 430 is a type of soft magnetic electromagnetic material with rapid magnetization and demagnetization properties. Considering the delay phenomenon during operation, this study selected 430 stainless steel as the material and explored various metallurgical methods such as magnetic annealing and the addition of Mo as well as increasing the Si content to investigate the microstructure, mechanical behavior, and magnetic properties of each material, aiming to improve the magnetic properties of 430 stainless steel. Experimental results showed that the four electromagnetic steel materials (430F, 430F-MA, 434, and KM31) had equiaxed grain matrix structures, and excellent tensile and elongation properties were observed for each specimen. Additionally, the magnetic properties of the 430F specimen were similar under the DC and AC-10 Hz conditions. According to the hysteresis curves under different AC frequencies (10, 100, 1000 Hz), both magnetic annealing and the addition of Mo could reduce the Bm, Br, and Hc values of the raw 430F material. Increasing the Si content resulted in a decrease in Hc values and an increase in Bm and Br values.

The influence of low nitrogen doping on bacterial adhesion of sputtered a-C:H coatings

Heavily dependent on both surface and bacteria characteristics, multiple and complex parameters control bacterial adhesion to any biomaterial surface. That's why there are so many contradictory results regarding the antibacterial and adhesion inhibition properties of Diamond-Like Carbon (DLC) protective coatings, despite the well-established biocompatibility of this very broad group of materials. Aiming at Orthodontics, this study reports the modification of hydrogenated amorphous carbon coatings (a-C:H), by nitrogen incorporation upon reactive magnetron sputtering. The effect of low N content up to 10 at.% on the microstructure and bacterial adhesion was studied. Despite the progressive graphitization upon doping, the surface roughness was not significantly influenced and the water contact angles remained above 70°. The adhesion of three bacterial strains of Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa was evaluated. The median colony forming units was lower on the a-C:H and a-C:H:N coatings in comparison to the bare AISI 316L medical grade stainless steel surface, regardless the bacterial strain. The best bacterial adhesion inhibition capacity was achieved for N doping of 6 at.%, without using any antibacterial agents.

Improving the technology of producing seamless hot‑rolled pipes from stainless steel l80 type 13Cr in the tube rolling workshop

The production of seamless hot‑deformed pipes from martensitic stainless steel with a high chromium content, used under the constant influence of aggressive environments, involves overcoming a series of technological challenges. These challenges are due to the metal’s structural features, such as relatively low plasticity, a narrow temperature range for hot deformation, a tendency to defect formation during rolling, and more intense wear on the rolling tools. The article discusses the main stages of research work on mastering the technology of producing seamless hot‑rolled pipes from stainless steel grade L80 type 13Cr at OJSC “BSW – Management Company of Holding “BMC”. It presents the results and complexities of mastering the technology for producing seamless stainless steel pipes, analyzes the results aimed at reducing the cost of finished products by increasing the durability of piercing mandrels, the resistance of disc saws for cutting blanks, eliminating metal adhesion to the piercing mill’s Dishar discs, increasing the productivity of the rolling line and heat treatment process.

Multi Responses Optimization of Wire Electrical Discharge Machining (WEDM) Parameters of Tool Steel Using Grey Relation Analysis

The aim of this work is to study the effects of several wire electrical discharge machining (WEDM) process parameters, such as the servo voltage (SV), the pulse on time (TON), and the pulse off time (TOFF) on the surface finish (SR) and the kerf width (KW) of stainless steel 304 as a workpiece material. A multi-responses optimization approach based on Grey relational analysis has been designed, and it was discovered that the main affecting factor is the pulse on time followed by the servo voltage. According to the data, the grey relation analysis (GRA) grade for the second trial, including (a servo voltage of 14V, a pulse on time of 100µs, and a pulse off time of 45µs), was the optimum combination of settings that may concurrently optimize all of the specified response qualities. By utilizing the regression analysis, the mathematical equations illustrating the link between the input parameters and the responses have been established. In particular, the findings of this article will assist manufacturing engineers in selecting an optimal set of process parameters for machining stainless steel (SS304) grade.

Effects of CuCr1Zr contamination on the tensile properties and microstructure of stainless steel 316L produced via laser powder bed fusion

AbstractCopper contamination has a negative effect on the tensile properties of certain stainless steel grades due to a weakening of grain boundaries via liquid metal embrittlement. This is especially problematic given current trends in laser powder bed fusion (L-PBF) that elevate contamination risks, such as multi-material processing or the use of recycled materials. As such, it is critical to establish composition limits for use in standard specifications. This study investigates the changes in tensile properties and cracking behavior in stainless steel alloy 316L contaminated with copper alloy CuCr1Zr at concentrations of 0–10 particle percent (pt.%) in horizontal, diagonal, and vertical build orientations. It is found that microcracks are already present at 1 pt.% Cu alloy and increase in density with contamination. The cracks are generally vertically oriented along columnar grain boundaries and are associated with high local Cu content, thus exacerbating the anisotropy of the as-built material. The contamination decreases the elastic modulus, yield strength (YS), ultimate tensile strength (UTS), and uniform elongation, eventually transitioning from ductile to brittle fracture modes. The build orientation relative to the tensile loading axis is shown to be a critical design parameter due to the preferential crack initiation and growth direction. The fracture surfaces at 10 pt.% contamination show regularly spaced, smooth brick-like cleavage patterns that correspond to the columnar grain dimensions. Even so, the measured YS and UTS exceeded the ASTM F3184-16 standard for CuCr1Zr contaminations up to 5 pt.%. As a conservative limit, it is proposed that a maximum content of 1 wt% Cu be specified for L-PBF SS316L.