Compression, mechanical properties

Compression set and durometer hardness are also important mechanical properties. Compression set is defined as the amount by which an elastomer fails to return to its original thickness after being subjected to a standard compressive load or deflection for a specified time at a specified temperature. A low percent compression set typifies a more compression resistant elastomeric formulation. Compression set of a closure on a sealed vial is a factor in maintaining the sterility and potency of the drug itself. 

The mechanical properties (compression strength and % compression) are determined by Instron Universal Testing Machine using a pellet of 20mm x 20mm pressed at a pressure of 1000kgcnf2 similar to the method used for plastics [68]. 

Horisawa E, Danjo K, Sunada H. Influence of granulating method on physical and mechanical properties, compression behaviour and compactibility of lactose and microcrystalline cellulose granules. Drug Dev Ind Pharm 2000 26 583-93. 

Specifications for the selection of the repair material should be based on tests that can be carried out prior to the application. Each test should be suitable to assess the performance of the materials with regard to the specific property that it is intended to evaluate. Several standards cover tests to be used for the evaluation of workability or mechanical properties (compressive, tensile or flexural strength, elastic modulus, adhesion) of the repair material. However, as far as durability performance is... 

The modification of cement concretes and mortars by polymers and resins is aimed at improvement of their mechanical properties compressive and tensile strengths, matrix-reinforcement bond, impermeability, corrosion resistance, etc. There are three main groups of polymer modified concretes ... 

Will be degraded by microcracking associated with irradiation swelling Mechanical Properties (Compressive Strength)... 

Workers at the Chinese university of Yangzhou [35] have used microwaves to modify the surface of waste rubber crumb by devulcanising it and then blending it with NR in various proportions. These mixtures were then vulcanised and the mechanical properties, compression set, swelling behaviour and crosslink density investigated. The results obtained were compared with those of blends that had been prepared using crumb that had not been treated with microwaves. 

Tomas J Product design of cohesive powders—mechanical properties, compression and flow behavior, Chem Eng Technnol 27 605-618, 2004. 

Pal] reported mechanical properties (compressive yield strength (0.2%) and creep) and oxidation behavior of Fe-(10-43.5) at.% Al-(10-33) at.% Ti alloys in the temperature range of 20 to 1100°C. The microstracture of these alloys after heat treatment at 800, 900 and 1000°C were either single phase (L2i or C14) or two-phase (L2i -1- C14 or B2 + 72 (Mn23The)). The ductile to brittle transition temperature (DBTT) falls between 675 and 900°C. Oxidation behavior of some alloys at 900C exhibits parabolic behavior. 

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