Mechanical Property of Bio-material. Physical Properties of Bio-Materials (III-B). Poching Wu, Ph.D. Department of Bio-Mechatronic Engineering National Ilan University. Compression Test.
Physical Properties of Bio-Materials (III-B)
Poching Wu, Ph.D.
Department of Bio-Mechatronic Engineering
National Ilan University
Where = deformation, m
Most bone cross sections can be modeled as either a hollow ellipse or a quadrant of an ellipse. The moment of Inertia for a hollow ellipse is:
WhereB = outside major diameter , m
b = inside major diameter , m
D = outside minor diameter , m
d = inside minor diameter , m
Where D = the central indentation
k’, n’ = constants
Where e = the coefficient of restitution
W = sample weight
H = height of drop
The mechanical parameters considered were potential energy, energy consumed, and rebound of the impacting product.
The force necessary to attain deformation; given as the final peak of the TPA curve, which is the force value corresponding to the first major peak. The maximum force during the first cycle of compression. Is also known as the “firmness”.
The force which the material fractures (height of first significant break in the peak of TPA curve); a sample with a high degree of hardness and low cohesiveness will fracture This can also de called Brittleness. Fracturability is the force value corresponding to the fracturability peak (if there is one).
The height that the food recovers during the time that elapses between the end of the first cycle and the start of the second cycle.
The rate at which a deformed sample goes back to its un-deformed condition after deforming force This can also de called Elasticity.
Defined as the distance that the product is extended during de-compression before separating from the probe.
The quantity to simulate the strength internal bonds making up the body of the sample; if Adhesiveness < Cohesiveness then probe would remain clean as the product has the ability to hold together.
The quantity to simulate the work necessary to overcome the attractive forces between the surfaces of the sample and surface of the probe with which the sample comes into contact; if Adhesiveness > Cohesiveness，then part of the sample will adhere to the probe.
The quantity to simulate the energy required to masticate a semi-solid sample to steady state of swallowing; (Hardness × Cohesiveness × Adhesiveness).
The quantity to simulate the energy required to disintegrate a semi-solid sample to a steady state of swallowing; (Hardness × Cohesiveness).