Sökning: "Ni-base superalloys"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden Ni-base superalloys.

  1. 1. Powder bed fusion processing of Ni-base superalloys - Defect formation and its mitigation

    Författare :Hans Gruber; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hot isostatic pressing; Ni-base superalloys; non-metallic inclusions; cracking; additive manufacturing; laser powder bed fusion; defect formation; Alloy 718; powder re-use; IN-738LC;

    Sammanfattning : Powder bed fusion of Ni- and Ni-Fe-base superalloys is actively considered a promising manufacturing technology for critical components for the aerospace and industrial gas turbine industries. Such components often operate under harsh conditions, and hence, high demands are placed on both process and feedstock material to meet the strict safety and long-term reliability requirements. LÄS MER

  3. 2. Laser powder bed fusion processing and heat treatment of Ni-base superalloys: microstructure and properties

    Författare :Abdul Shaafi Shaikh; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microstructure.; Additive manufacturing; heat treatment; Inconel 939; Haynes 282; superalloys; powder bed fusion – laser beam;

    Sammanfattning : Nickel-base superalloys are indispensable materials for the energy and aerospace industries. The additive manufacturing (AM) of these materials by powder bed fusion – laser beam (PBF-LB) presents a valuable opportunity to improve component performance and ease manufacturing and supply chain complexity in these industries. LÄS MER

  4. 3. Microstructural evolution during hot compression of a Ni-base superalloy: Dynamic and post-dynamic recrystallization below the secondary carbide solvus temperature

    Författare :Emil Eriksson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hot compression; Ni-base superalloys; Electron microscopy; Recrystallization;

    Sammanfattning : With an increased demand to lower emissions, the eciency of aircraft engines have to be improved. One way to achieve this is to increase the operation temperature. However, due to the extremely challenging environments in the hot sections of these engines, the current alloys are at their limits. LÄS MER

  5. 4. Oxygen Induced High Temperature Crack Growth in Ni-base Superalloys

    Författare :Leif Viskari; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Diffusion; Environmental influence; Crack growth; Atom probe tomography; Electron Microscopy; Deformation; Crack tip oxidation; Hold-time fatigue;

    Sammanfattning : Oxygen induced crack growth is a serious concern for the performance of Ni-base superalloys. These alloys are used in gas-turbine engines where they are exposed to hightemperatures, mechanical loads and oxygen-rich environments. LÄS MER

  7. 5. Dynamic and meta-dynamic recrystallization of Ni-based superalloy Haynes 282

    Författare :Emil Eriksson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hot compression; EBSD; dynamic recrystallization; meta-dynamic recrystallization; Ni-base superalloys;

    Sammanfattning : Thermomechanical processes are a crucial manufacturing step because they can “reset” the microstructure, and set the starting point for all following steps. In turn, the microstructure can be used to tailor the mechanical properties of the material. LÄS MER