Plain bearings - Hardness testing of bearing metals

Tablets are one of the most popular and preferred solid dosage forms because they can be accurately dosed, easily manufactured and packaged on a large scale, have good physical and chemical stability, and can contribute to good patient compliance given their ease of administration. The ability to match doses to patients depends on the availability of multiple dose sizes and adequate dose-response information. These are not always provided, so splitting of the tablets is sometimes necessary, Tablet splitting is an accepted practice in dispensing medication, It has been used when a dosage form of the required strength is not available commercially. The aim of our study was to compare some physical parameters of whole and scored lisinopril and lisinopril/hydrochlorthiazide tablets and to accept or exclude their influence on the obtaining of required dosage.According to the results obtained, we may conclude that tablets from batch “I” “IL “III” and “IV” satisfied pharmacopeial requirements concerning crushing strength, friability, disintegration time and mass uniformity. The hardness testing showed acceptable reproducibility and indicate that the data variation was primarily from the irreversible changes in the structure of tablet samples. The act of compacting powders stores energy within the tablets, by shifting or compressing the intermolecular bonds within the particles. The tablets have a natural tendency to relax once pressure is removed, and this tendency works against the interparticle bonding formed during compression. Hardness testing procedure causes irreversible changes in this structure.

Download Full-text

Kalibriernormal für Geräte der registrierenden Härteprüfung (Standard for Calibration of Instruments of Hardness Testing)

tm - Technisches Messen ◽

10.1524/teme.2007.74.7-8.385 ◽

2007 ◽

Vol 74 (07-08) ◽

Cited By ~ 3

Author(s):

Joachim Frühauf ◽

Eva Gärtner ◽

Konrad Herrmann ◽

Febo Menelao

Keyword(s):

Hardness Testing

Download Full-text

Basic Studies of Plastic Working with Vibration : 2nd Report, Basis of Vibro-Indentation Hardness Testing

Bulletin of JSME ◽

10.1299/jsme1958.17.1547 ◽

1974 ◽

Vol 17 (114) ◽

pp. 1547-1554

Author(s):

Masao MIZUNO ◽

Takahiko KUNO ◽

Shigetoshi MIYAZAWA ◽

Hiromi NAKANISHI ◽

Toyoichiro NOJIMA ◽

...

Keyword(s):

Indentation Hardness ◽

Hardness Testing ◽

Plastic Working ◽

Basic Studies

Download Full-text

Elastic/plastic effects during very low-load hardness testing of copper

Acta Metallurgica et Materialia ◽

10.1016/0956-7151(94)00291-o ◽

1995 ◽

Vol 43 (3) ◽

pp. 1037-1043 ◽

Cited By ~ 16

Author(s):

R.W. Armstrong ◽

H. Shin ◽

A.W. Ruff

Keyword(s):

Hardness Testing ◽

Elastic Plastic ◽

Low Load

Download Full-text

Influence of High Temperature Annealing on Microstructure Evolution of Ni-24Fe-14Cr-8Mo Superalloy

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.904.117 ◽

2021 ◽

Vol 904 ◽

pp. 117-123

Author(s):

Yi Cui ◽

Yun Fei Zhang ◽

Yan Guang Han ◽

Da Lv

Keyword(s):

High Temperature ◽

Microstructure Evolution ◽

Testing Machine ◽

Aging Treatment ◽

Growth Patterns ◽

High Temperature Annealing ◽

Rockwell Hardness ◽

Hardness Testing ◽

X Ray Diffraction ◽

X Ray

The effect of high temperature annealing on microstructure evolution of Ni-24Fe-14Cr-8Mo alloy was investigated through Optical Microscopy (OM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Rockwell Hardness Testing Machine. Three kinds of grain growth patterns were found at different annealing temperatures due to carbides precipitation and dissolution. After a combination of high temperature annealing and aging treatment, the hardness versus time curves performed a parabolic pattern. The highest hardness was achieved under 1070°C/60 minutes treatment, and the desirable annealing time should be 60 minutes to 90 minutes.

Download Full-text