A high strength nickel-base alloy with improved oxidation resistance up to 2200 deg F.
High strength nickel base alloy with improved oxidation resistance up to 2200 degrees F for applicability to gas turbine engine components
OXIDATION RESISTANCE↗
SEARCH · Engineering Papers
Results for “high strength”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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A high strength Al-2Ni-0.5Zr conductor alloy fabricated via laser powder bed fusion
There is a current need for new aluminum alloy design strategies to target applications requiring high strength and conductivity with reductions in mass. A new lightweight Al-2Ni-0.5Zr (wt. %) conductor alloy was fabricated using laser powder bed fusion. A design of experiments probed the alloy's solidification cracking susceptibility. It was observed that solidification cracking was generally reduced with fast scan speeds, above 1500 mm/s, and smaller hatch spacings. The different cooling rates throughout the melt pool produced a heterogeneous distribution of cellular and equiaxed Al 3 Ni precipitates in the as-printed alloy. Additionally, the rapid solidification characteristic of laser powder bed fusion created a super-saturated Zr solid solution. An aging heat treatment at 375 °C for 24 h imparted strengthening through the precipitation of L1 2 -Al 3 Zr nanoprecipitates, which counteracted the softening caused by the fragmentation and coarsening of Al 3 Ni precipitates. The yield strength increased from 138 MPa in the as-printed condition to 168 MPa after aging, while the ductility remained constant at ∼21%. The aging treatment simultaneously increased the electrical conductivity from 40.8% IACS (International Annealed Copper Standard) to 53.5% IACS. Modeling of the strengthening mechanisms and electrical conductivity contributions rationalized the simultaneous increase in strength and conductivity upon aging. Furthermore, the strengthening efficacy of the Al 3 Ni and L1 2 -Al 3 Zr precipitates, combined with the low Ni and Zr solubility in the FCC Al matrix, facilitated both high strength and electrical conductivity. Overall, the combination of strength and electrical conductivity positions this alloy as a suitable choice for additively manufactured lightweight conductors.
Additive manufacturing↗
Crack mitigation and wear performance of high-strength steel coatings deposited by high-speed laser cladding
This article investigates the fabrication of defect-free Rockit® 606, a high‑carbon, vanadium- and chromium-enriched precipitation-hardening martensitic steel coating, using high-speed laser cladding (HSLC). Compared to conventional laser cladding, HSLC offers higher deposition efficiency, improved coating quality, minimal thermal distortion, and a reduced heat-affected zone. Various HSLC parameters—including laser power, travel speed, powder feed rate, and overlap distance—were optimized to achieve superior coating properties. Microstructural analysis revealed solidification cracks in coatings deposited on carburized steel, regardless of processing parameters. However, preheating the substrate to 250 °C effectively eliminated cracking by reducing thermal gradients. The coatings exhibited a columnar dendritic microstructure, with coarser dendrites near the substrate and finer dendrites towards the surface. Hardness measurements confirmed that all coatings significantly exceeded the industry-specified threshold of 60 HRC, with preheating having minimal effect on overall hardness distribution. Reciprocating sliding wear tests demonstrated a substantial improvement in wear resistance for the defect-free HSLC coatings compared to baseline carburized steel. These findings underscore the potential of HSLC for producing high-performance, wear-resistant coatings suitable for industrial applications.
36 MATERIALS SCIENCE↗
Ta-containing Fe-Ni based superalloys with high strength and oxidation resistance for high-temperature applications
A Fe—Ni based alloy comprising, in weight percent: Ni 30-35; Cr 12-14; Al 3-5; Ti 0-2; Ta 2-8; C<=0.05; B<=0.005; Zr<=0.2; Si<0.5; where Cr/(Cr+Fe+Ni)=0.125-0.145; Al/(Al+Ti+Ta)=0.15-0.5; and Fe≥Ni; balance Fe, the alloy having a face-centered cubic (fcc) matrix with from 25 to 30 vol. % of L12-type γ′-Ni3M (M=Al, Ta, Ti and mixtures thereof) precipitates.
Yang, Ying↗
DEM analysis of the effect of interface transition zone on dynamic splitting tensile behavior of high-strength concrete based on multi-phase model
Highlights: • Crushable aggregates with the real geometry shape are generated by using clump-cluster method. • Flat-Joint Model is adopted as the constitutive law. • The tensile strength is almost not affected by ITZ strength when its strength exceeds 0.8 times that of mortar. • A modified formula that can reflect the functional relationship between the ITZ strength and the TDIF is proposed. The tensile strength is one of the main parameters in the design of concrete structures and has an important influence on the cracking performance and durability of concrete materials. As the weak region in concrete, the strength of the interface transition zone (ITZ) directly affects the dynamic mechanical response of concrete. Meanwhile, considering that the tensile performance of concrete is far weaker than its compressive performance, the study of the strength of ITZ is of great significance to the dynamic tensile fracture characteristics and mechanical properties of concrete. In this paper, a method combining 3D scanning technology and Clump-Cluster was proposed to generate a real geometry shape model of crushable aggregate. On this basis, the 3D discrete element model (DEM) of high-strength concrete was constructed using the Flat-Joint Model (FJM). The effects of the ITZ strength on the failure mode, number of microcracks, tensile strength and strain rate effect of high-strength concrete under strain rates from 0.01/s to 100/s were studied by splitting tensile test. The simulation results indicate that the number of microcracks generated decreases with the increase of ITZ strength, and the proportion of ITZ cracks decreases obviously. When the ITZ strength exceeds the critical value of 0.8 times that of mortar, the tensile strength is almost not affected by ITZ strength. In addition, based on the numerical simulation results, a modified formula that can reflect the functional relationship between the ITZ strength and the dynamic increasing factor of the concrete tensile strength (TDIF) is proposed, and the rationality of the TDIF modified formula is verified.
36 MATERIALS SCIENCE↗
Prioritization of Early-Stage Research and Development of a Hydrogel-Encapsulated Anaerobic Technology for Distributed Treatment of High Strength Organic Wastewater
This study aims to support the prioritization of research and development (R&D) pathways of an anaerobic technology leveraging hydrogel-encapsulated biomass to treat high-strength organic industrial wastewaters, enabling decentralized energy recovery and treatment to reduce organic loading on centralized treatment facilities. To characterize the sustainability implications of early-stage design decisions and to delineate R&D targets, an encapsulated anaerobic process model was developed and coupled with design algorithms for integrated process simulation, techno-economic analysis, and life cycle assessment under uncertainty. Across the design space, a single-stage configuration with passive biogas collection was found to have the greatest potential for financial viability and the lowest life cycle carbon emission. Through robust uncertainty and sensitivity analyses, we found technology performance was driven by a handful of design and technological factors despite uncertainty surrounding many others. Hydraulic retention time and encapsulant volume were identified as the most impactful design decisions for the levelized cost and carbon intensity of chemical oxygen demand (COD) removal. Encapsulant longevity, a technological parameter, was the dominant driver of system sustainability and thus a clear R&D priority. Ultimately, we found encapsulated anaerobic systems with optimized fluidized bed design have significant potential to provide affordable, carbon-negative, and distributed COD removal from high strength organic wastewaters if encapsulant longevity can be maintained at 5 years or above.
Anaerobic Treatment↗
Investigation of the stress-corrosion cracking of high strength aluminum alloys Summary report, May 6, 1963 - Jul. 6, 1965
Stress corrosion cracking of high strength aluminum alloys
HIGH STRENGTH ALLOY↗
Bulk nanocrystalline Al–Mg–Y alloys with amorphous grain boundary complexions display high strength and compressive plasticity
Although nanocrystalline alloys regularly exhibit high strengths, their use in structural applications often face challenges due to sample size limitations, unstable microstructures, and the limited ability to plastically deform. The incorporation of amorphous grain boundary complexions has been proposed to address these issues, by simultaneously stabilizing nanocrystalline grain structures for scale-up processing and improving alloy toughness. In the present study, the mechanical behavior of bulk nanocrystalline Al–Mg–Y is examined with macroscale compression testing, probing a length scale that is relevant to real-world structural applications. Bulk samples were fabricated via a simple powder metallurgy approach, with different hot-pressing temperatures and durations employed for consolidation in order to investigate microstructural and property evolution. All of the specimens contained primary face-centered cubic Al and secondary Al 4 C 3 and Al 3 Y phases, with the Al 3 Y particles exhibiting two populations of small equiaxed and larger elongated particles. Appreciable plasticity was measured along with high ultimate stresses over 800 MPa due to the presence of amorphous grain boundary complexions. Microstructural characterization of fracture surfaces revealed that the area fraction of dimpled regions increased with longer hot-pressing time. Most importantly, the elongated Al 3 Y particles formed regular cellular patterns with increasing hot-pressing time, delaying shear localization and significantly enhancing plasticity. The hierarchy present in the microstructure of the Al–Mg–Y alloy, from amorphous grain boundary complexions to secondary phases, gives rise to excellent bulk mechanical properties, which are attractive for structural applications.
Bulk nanocrystalline alloy↗
Intermetallic particle heterogeneity controls shear localization in high-strength nanostructured Al alloys
The mechanical behavior of two nanocrystalline Al alloys, Al-Mg-Y and Al-Fe-Y, is investigated with in-situ micropillar compression testing. Both alloys were strengthened by a hierarchical microstructure including grain boundary segregation, nanometer-thick amorphous complexions, carbide nanorod precipitates with sizes of a few nanometers, and submicron-scale intermetallic particles. The maximum yield strength of the Al-Mg-Y system is measured to be 950 MPa, exceeding that of the Al-Fe-Y system (680 MPa), primarily due to a combination of more carbide nanorods and more amorphous complexions. Both alloys exhibited yield strengths much higher than those of commercial Al alloys, and therefore have great potential for structural applications. However, some micropillar specimens were observed to plastically soften through shear banding. Post-mortem investigation revealed that intermetallic-free deformation pathways of a few micrometers in length were responsible for this failure. Further characterization showed significant grain growth within the shear band. The coarsened grains maintained the same orientation with each other, pointing to grain boundary mechanisms for plastic flow, specifically grain rotation and/or grain boundary migration. Here, the presence of intermetallic particles makes it difficult for both matrix and intermetallic grains to rotate into the same orientation due to the different lattice parameters and slip systems. Therefore, we are able to conclude that a uniform distribution of intermetallic particles with an average spacing less than the percolation length of shear localization can effectively prevent the maturation of shear bands, offering a design strategy for high-strength nanocrystalline Al alloys with both high strength and stable plastic flow.
36 MATERIALS SCIENCE↗
Evaluation of high strength columbium alloys for alkali metal containment Final report, 25 Jul. 1962 - 15 Dec. 1964
High strength niobium alloy corrosion testing and evaluation of alkali metal containment
METAL CORROSION↗
Development of a Compact, Low Cost Test Fixture to Evaluate Creep in High Strength Softgoods Materials under Constant Environmental Control
Space exploration is typically driven by two key factors: cost and payload mass. Therefore creating relatively low cost, low mass space hardware is critical. With the advancement of new high-strength flexible materials, a new chapter is opening in the evolution of pressurized space structures. Space-rated inflatable structures are attractive due to their low mass, compact stowage, and capability of performing as well, or better than, their rigid counterparts for applications such as habitats and airlocks. The lifetime properties of materials used for inflatable structures are not as well characterized as heritage composite and metallic materials; therefore, they require extensive testing to increase the level of confidence in their use. Creep testing is one method of evaluating the expected lifetime of materials that may be under constant load for many years in operational use. Conventional creep testing of high-strength softgoods webbings or cordage requires a large, temperature-controlled facility, with structural frames capable of supporting large dead weights, weighing thousands of pounds on each specimen. This is expensive and takes up a significant amount of volume in a facility for a long time. This paper describes the design and analysis of a low-cost, low-volume creep test stand that can be locally environmentally controlled, so that smaller, cheaper facilities can be used for characterizing the creep life of the softgoods materials used in inflatable space structures.
Softgoods↗
Develop a new integrated macro→micro←nano (MMN) multiscale modeling framework to optimize high strength aluminum alloys and processes for vehicle light-weighting
Bending tests provide a means to study plane strain fracture performance of 6000 series aluminum alloys. Metrics from bending tests have been correlated with self-pierce riveting (SPR) performance of a high strength AA6111 automotive aluminum alloy in previous works. Using the ORNL HPC resources, this project developed an innovative macro→micro←nano (MMN) multiscale microstructure-based finite element (FE) code to further the understanding of microstructural relationship to fracture properties of high strength 6000 series alloys.
36 MATERIALS SCIENCE↗
Joining of High Strength Low Ductility AA7055 by Friction Self-piercing Rivet
High strength aluminum (Al) alloy is one of higher specific strength materials for decarbonization in transportation industries. Because of low ductility at room temperature, conventional mechanical fastening such as self-piercing riveting produces cracks at the joint. In this work, we applied friction self-piercing riveting to join Al alloy (AA) 7055. No cracks were observed in the joints because of the improved local ductility of Al alloy by the generated frictional heat during joining step. Numerical modeling of joining process was applied to guide rivet geometry design and rivet material strength. Mechanical integrity of the AA7055 joints was assessed by lap shear tensile and cross-tension testing. Metallurgical characterizations revealed solid-state bonding formed not only between the rivet and surround Al materials, but also upper and lower Al sheets at the joint interface. Both solid-state bonding and mechanical interlocking between the flared rivet and bottom AA7055 sheet were the major joint mechanisms.
Lim, Yong Chae↗
Amorphous complexion-aided sintering enables scalable processing of bulk nanocrystalline Cu-Zr with high strength and compressive plasticity
Nanocrystalline alloys can have exceptional strengths, yet due to limited microstructural stability it is difficult to fabricate bulk pieces through traditional processing routes that retain nanosized grains. In this study, centimeter-sized Cu-Zr alloy pellets were fabricated via a simple and improved powder metallurgy processing route. Different consolidation temperatures and times were employed to investigate the effect of amorphous grain boundary complexions on densification and the resulting mechanical properties. Bulk compression tests were carried out, with the samples that were hot pressed at 900 °C for 10 h exhibiting an excellent combination of average yield strength of 722 ± 45 MPa and average failure strain of 25.3 ± 2.4 %. Furthermore, we find that a powder processing route which enables amorphous complexion-assisted sintering leads to samples that (1) reach full density without requiring quenching treatments or other complex processing, (2) demonstrate appreciable plasticity, and (3) have strength that competes with commercially available high-strength Cu alloys.
Bulk nanocrystalline alloy↗
The effect of high-gradient, high-strength magnetic fields on the early embryonic development of frogs
High strength magnetic fields effect on early embryonic development of frogs, relating growth abnormalities and paramagnetic ferritin motions
Neurath, P. W.↗
An investigation of the plastic fracture of high strength steels
Three generally recognized stages of plastic fracture in high strength steels are considered in detail. These stages consist of void initiation, void growth, and void coalescence. A brief review of the existing literature on plastic fracture is included along with an outline of the experimental approach used in the investigation.
Cox, T. B.↗
A Novel Method for Electroplating Ultra-High-Strength Glassy Metals
A novel method for electroplating ultra-high-strength glassy metals, nickel-phosphorous and nickel-cobalt-phosphorous, has been developed at NASA Marshall Space Flight Center, cooperatively with the University of Alabama in Huntsville. Traditionally, thin coatings of these metals are achieved via electroless deposition. Benefits of the new electrolytic process include thick, low-stress deposits, free standing shapes, lower plating temperature, low maintenance, and safer operation with substantially lower cost.
Ramsey, Brian↗
Development of welding techniques and filler metals for high strength aluminum alloys Annual summary report, 27 Jun. 1964 - 27 Jun. 1965
Welding techniques and filler metals for high strength aluminum alloys
HIGH STRENGTH ALLOY↗