PURPOSE This study was aimed to determine the effect of two chemically distinct denture cleansers and water on the surface hardness of acrylic and silicone based soft denture liners at various time intervals. MATERIALS AND METHODS Two commonly used commercial resilient liner material were selected based on their chemical composition (silicone- and acrylic-based soft liners) for this investiga...

Surfaces of boron carbide (B4C) were implanted with 200 keV N: or 100 keV AI + ions to a dose of 8 x 10” cm‘. Ultralow load indentation via the Nanoindenter was used to determine the changes in surface hardness and elastic modulus following implantation. A pin-on-disk testing device in ultrahigh vacuum was used for measuring changes in friction and wear of the implanted disks. Results of hardne...

PURPOSE The purpose of this study was to investigate the effect of different plasticizing aging solutions on wear resistance and hardness of selected universal resin-based dental composites. METHODS Three light cured (one nanofilled, two microhybride) and one hybride chemical cured composites were aged at 37 °C for 48 h in distillated water, ethyl alcohol solution or Listerine mouthwash. Afte...

WANTED: MEASUREMENTS WITH GOOD REFERENCES In nearly all types of activities-be they related to manufacturing, finance, health, regulatory affairs or even sports-people and organizations are becoming sticklers for measurement uncertainty. NIST, the nation’s measurement authority, has responded to this growing customer need for demonstrable uncertainty. It has created an on-line resource— www.nis...

In this research, the effect of vibration at the resonant range (75 Hz) on the hardness and tensile strength of AA-5083-H321 aluminum alloy, were welded by gas metal arc welding (GMAW) investigated. Vibration forces were ranged from 850 N to 2200 N, under identical welding parameters. Tensile strength and hardness testing of welded samples were performed. After mechanical tests, the fracture su...

Here we describe modifications that allow the bone diagnostic instrument (BDI) [P. Hansma et al., Rev. Sci. Instrum. 79, 064303 (2008); Rev. Sci. Instrum. 77, 075105 (2006)], developed to test human bone, to test the femora of mice. These modifications include reducing the effective weight of the instrument on the bone, designing and fabricating new probe assemblies to minimize damage to the sm...

The current paper is focussed on the nodular cast iron ASTM 80-55-06 (EN-GJS-600). The individual microstructure was investigated by light and scanning electron microscopy as well as micro-hardness measurements. Stress-controlled fatigue tests were performed at ambient temperature with testing frequencies of f = 5 Hz and f = 150 Hz. The cyclic deformation behaviour was characterised by means of...