National Repository of Grey Literature 2 records found  Search took 0.00 seconds. 
Wear analysis of the sliding surface material of large-scale hydrostatic bearings
Daněk, Lukáš ; Robenek, Dětřich (referee) ; Svoboda, Petr (advisor)
This thesis focuses on the experimental investigation of the wear behavior of sliding surface materials in large-scale hydrostatic bearings during oil supply failure. The aim is to clarify the influence of materials and surface treatments on friction and wear. For this purpose, a testing methodology was designed and implemented in laboratory conditions. An experimental module was developed for the tribometer to simulate a critical state and a new procedures were established for evaluating the behavior of the contact. Wear results were observed using a profilometer, precise scales, and a microscope. A set of suitable materials for pad sliding surfaces was created, which were tested under critical conditions. The selected materials were representatives of construction steel and anticorrosion treatments (galvanization), soft and hard (aluminium) bronzes, composite bearing linings (Babbitt), polymers (UHMWPE), and composite materials (PTFE). The experimental results show the dependence of friction on sliding velocity, wear rate, and other phenomena repeatedly measured on a statistical sample of selected materials. The final result is a list of characteristics, limitations, and recommendations for the tested sliding materials, which can be used for more effective design and operation of large-scale hydrostatic bearings.
Review of the options and methods of manufacture polyethylene acetabular cups artificial hip joint
Klus, Patrik ; Ficza, Ildikó (referee) ; Ranuša, Matúš (advisor)
The bachelor‘s thesis gives a complex review of options and methods for manufacturing polyethylene acetabular liners in artificial joint hips. It describes the development process of polyethylene from the early 70s to nowadays. Several manufacturing techniques of polyethylene liners and their effect on the wear resistance are also listed. The final part of the thesis focuses on older and modern evaluation methods of linear or volumetric wear rate of polyethylene liners.