EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Engine Structures

Download or read book Engine Structures written by and published by . This book was released on 1988 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Scientific and Technical Aerospace Reports

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book NASA Technical Memorandum

Download or read book NASA Technical Memorandum written by and published by . This book was released on 1988 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Micromechanisms of Low Cycle Fatigue in Nickel Based Superalloys at Elevated Temperatures

Download or read book Micromechanisms of Low Cycle Fatigue in Nickel Based Superalloys at Elevated Temperatures written by RM. Pelloux and published by . This book was released on 1979 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The micromechanisms of high-temperature fatigue crack initiation and crack propagation in solid-solution and precipitation-strengthened nickel-base super-alloys are reviewed. The marked decrease in fatigue strength of a given superalloy with increasing temperature cannot be solely correlated with the temperature dependence of the short-time mechanical properties. The interactions between oxidation rates and fatigue strengths are very complex. The air environment plays a large role in accelerating the initiation and propagation of fatigue cracks at elevated temperatures. Increasing temperature and decreasing frequency lead to a transition from transgranular to intergranular fracture path.

Book High Temperature Low Cycle Fatigue of Copper base Alloys in Argon Part 3 Zirconium copper Thermal mechanical Strain Cycling Hold time and Notch Fatigue Results

Download or read book High Temperature Low Cycle Fatigue of Copper base Alloys in Argon Part 3 Zirconium copper Thermal mechanical Strain Cycling Hold time and Notch Fatigue Results written by and published by . This book was released on 1973 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Monthly Catalogue United States Public Documents

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1983 with total page 1050 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Methods for Predicting Material Life in Fatigue

Download or read book Methods for Predicting Material Life in Fatigue written by American Society of Mechanical Engineers and published by . This book was released on 1979 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Energy Research Abstracts

Download or read book Energy Research Abstracts written by and published by . This book was released on 1990 with total page 852 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Alloy Design and Characterization of Strengthened Nickel based Superalloys for Additive Manufacturing

Download or read book Alloy Design and Characterization of Strengthened Nickel based Superalloys for Additive Manufacturing written by Jinghao Xu and published by Linköping University Electronic Press. This book was released on 2021-01-28 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nickel-based superalloys, an alloy system bases on nickel as the matrix element with the addition of up to 10 more alloying elements including chromium, aluminum, cobalt, tungsten, molybdenum, titanium, and so on. Through the development and improvement of nickel-based superalloys in the past century, they are well proved to show excellent performance at the elevated service temperature. Owing to the combination of extraordinary high-temperature mechanical properties, such as monotonic and cyclic deformation resistance, fatigue crack propagation resistance; and high-temperature chemical properties, such as corrosion and oxidation resistance, phase stability, nickel-based superalloys are widely used in the critical hot-section components in aerospace and energy generation industries. The success of nickel-based superalloy systems attributes to both the well-tailored microstructures with the assistance of carefully doped alloying elements, and the intently developed manufacturing processes. The microstructure of the modern nickel-based superalloys consists of a two-phase configuration: the intermetallic precipitates (Ni,Co)3(Al,Ti,Ta) known as γ′ phase dispersed into the austenite γ matrix, which is firstly introduced in the 1940s. The recently developed additive manufacturing (AM) techniques, acting as the disruptive manufacturing process, offers a new avenue for producing the nickel-based superalloy components with complicated geometries. However, γ′ strengthened nickel-based superalloys always suffer from the micro-cracking during the AM process, which is barely eliminated by the process optimization. On this basis, the new compositions of γ′ strengthened nickel-based superalloy adapted to the AM process are of great interest and significance. This study sought to design novel γ′ strengthened nickel-based superalloys readily for AM process with limited cracking susceptibility, based on the understanding of the cracking mechanisms. A two-parameter model is developed to predict the additive manufacturability for any given composition of a nickel-based superalloy. One materials index is derived from the comparison of the deformation-resistant capacity between dendritic and interdendritic regions, while another index is derived from the difference of heat resistant capacity of these two spaces. By plotting the additive manufacturability diagram, the superalloys family can be categorized into the easy-to-weld, fairly-weldable, and non-weldable regime with the good agreement of the existed knowledge. To design a novel superalloy, a Cr-Co-Mo-W-Al-Ti-Ta-Nb-Fe-Ni alloy family is proposed containing 921,600 composition recipes in total. Through the examination of additive manufacturability, undesired phase formation propensity, and the precipitation fraction, one composition of superalloy, MAD542, out of the 921,600 candidates is selected. Validation of additive manufacturability of MAD542 is carried out by laser powder bed fusion (LPBF). By optimizing the LPBF process parameters, the crack-free MAD542 part is achieved. In addition, the MAD542 superalloy shows great resistance to the post-processing treatment-induced cracking. During the post-processing treatment, extensive annealing twins are promoted to achieve the recrystallization microstructure, ensuring the rapid reduction of stored energy. After ageing treatment, up to 60-65% volume fraction of γ′ precipitates are developed, indicating the huge potential of γ′ formation. Examined by the high-temperature slow strain rate tensile and constant loading creep testing, the MAD542 superalloy shows superior strength than the LPBF processed and hot isostatic pressed plus heat-treated IN738LC superalloy. While the low ductility of MAD542 is existed, which is expected to be improved by modifying the post-processing treatment scenarios and by the adjusting building direction in the following stages of the Ph.D. research. MAD542 superalloy so far shows both good additive manufacturability and mechanical potentials. Additionally, the results in this study will contribute to a novel paradigm for alloy design and encourage more γ′-strengthened nickel-based superalloys tailored for AM processes in the future.

Book Physics Briefs

Download or read book Physics Briefs written by and published by . This book was released on 1985 with total page 986 pages. Available in PDF, EPUB and Kindle. Book excerpt: