Đang chuẩn bị liên kết để tải về tài liệu:
Coatings Technology Handbook Episode 1 Part 2

Tham khảo tài liệu 'coatings technology handbook episode 1 part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 2-4 Coatings Technology Handbook Third Edition TABLE 2.2 Some Commercially Available Rheological Instrumentation Name of Instrument Geometries Available Shear-Rate Range Modes Available Weissenberg Rheogoniometer Couette cone and plate Broad Steady shear oscillatory Rheometrics Mechanical parallel plate Couette plate and cone Broad Steady shear oscillatory Spectrometer Carri-Med Controlled Stress parallel plate Couette parallel plate Fixed stress Creep and recovery oscillatory Rheometer CSR Rheo-Tech Viscoelastic Cone and plate Fixed stress Oscillatory creep and recovery Rheometer VER Contraves Rheomat 115 Cone and plate couette Broad Steady shear Rheometrics Stress Rheometer Cone and plate Fixed stress Oscillatory creep and recovery Haake Rotovisco Couette cone and plate Broad Steady state Shirley-Ferranti Cone and plate Broad Steady shear ICI Rotothinner Couette Single high rate Steady shear Brookfield Cone and Plate Cone and plate Medium to high Steady Brookfield Spindle Undefined Undefined Steady shear Gardner-Holdt Rising bubble Undefined Cannon-Ubbelohde Poiseuille Limited range high end Shear Brushometer Couette High end only single Steady shear of coating rheology. If meaningful correlations are to be made with coating phenomena the viscosity must be measured over a wide range of strain rates. The most acceptable technique for determining the strain-rate dependence of the viscosity is the use of the constant rate-of-strain experiment in torsion. This can be done in either a cone-and-plate for low rates or a concentric cylinder geometry for higher rates . However the oscillatory or dynamic measurement is also commonly employed for the same purpose. It is assumed that the shear strain rate and the frequency are equivalent quantities and the complex viscosity is equal to the steady state constant rate viscosity i.e. the Cox-Merz rule is valid . The applicability of the Cox-Merz rule however is by no means universal and its validity must be demonstrated before