**Flow stress** is defined as the instantaneous value of stress required to continue deforming the material - to keep the metal flowing. It is the yield strength of the metal as a function of strain, which can be expressed:

- Yf = Ken

- Yf = Flow stress, MPa
- e = True strain
- K = Strength Coefficient, MPa
- n = Strain hardening exponent

Hence, **Flow stress** can also be defined as the stress required to sustain plastic deformation at a particular strain.

The flow stress is a function of plastic strain.

Flow stresses occur when a mass of flowing fluid induces a dynamic pressure on a conduit wall. The force of the fluid striking the wall acts as the load. This type of stress may be applied in an unsteady fashion when flow rates fluctuate. Water hammer is an example of a transient flow stress.

The following properties that have an effect on flow stress: chemical composition, purity, crystal structure, phase constitution, exit microstructure, grain size, and heat treatment.

### Other articles related to "flow stress, stress":

**Flow Stress**Models - Preston–Tonks–Wallace

**Flow Stress**Model

... (PTW) model attempts to provide a model for the

**flow stress**for extreme strain-rates (up to 1011/s) and temperatures up to melt ... The PTW

**flow stress**is given by with where is a normalized work-hardening saturation

**stress**, is the value of at 0K, is a normalized yield

**stress**, is the hardening constant ... The saturation

**stress**and the yield

**stress**are given by where is the value of close to the melt temperature are the values of at 0 K and close to ...

**Flow Stress**Models - Mechanical Threshold Stress

**Flow Stress**Model

... The Mechanical Threshold

**Stress**(MTS) model ) has the form where is the athermal component of mechanical threshold

**stress**, is the component of the

**flow stress**due to ... The strain hardening component of the mechanical threshold

**stress**is given by an empirical modified Voce law where and is the hardening due to dislocation accumulation, is the ...

**Flow Stress**Models - Zerilli–Armstrong

**Flow Stress**Model

... The general form of the equation for the

**flow stress**is In this model, is the athermal component of the

**flow stress**given by where is the contribution due to solutes ...

### Famous quotes containing the words stress and/or flow:

“In the *stress* of modern life, how little room is left for that most comfortable vanity that whispers in our ears that failures are not faults! Now we are taught from infancy that we must rise or fall upon our own merits; that vigilance wins success, and incapacity means ruin.”

—Agnes Repplier (1858–1950)

“On the idle hill of summer,

Sleepy with the *flow* of streams,”

—A.E. (Alfred Edward)