Sökning: "Nils-Gunnar Ohlson"

Hittade 2 avhandlingar innehållade orden Nils-Gunnar Ohlson.

1. 1. Mechanical behaviour of a roller bearing steel : Strength differential effect, low temperature creep and propagation of short cracks

   Författare :Irene Linares Arregui; Bo Alfredsson; Nils-Gunnar Ohlson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Fatigue cracks in bearings either initiate from the surface or from an inclusion below the rolling contact surface. Then, short cracks start to propagate. Short crack grow at considerably faster rates than long cracks subjected to a nominally equivalent stress intensity factor range. LÄS MER

3. 2. Impact of Metallic Projectiles on a Ceramic Target Surface : Transition Between Interface Defeat and Penetration

   Författare :René Renström; Bengt Lundberg; Patrik Lundberg; Nils-Gunnar Ohlson; Uppsala universitet; []
   Nyckelord :Engineering physics; Projectile; Cylindrical; Conical; Yield strength; Compressibility; Perfect flow; Self-similar flow; Interface defeat; Dwell; Teknisk fysik; Teknisk fysik med inriktning mot hållfasthetslära; Engineering Science with specialization in Solid Mechanics;

   Sammanfattning : The purpose of this thesis is to gain understanding of the load on flat target surfaces produced by projectile impact. Models are proposed from which upper and lower bounds can be derived for the transition be-tween interface defeat and normal penetration. LÄS MER