Effects of R-Phase on Mechanical Responses of a Nickel-Titanium Endodontic Instrument: Structural Characterization and Finite Element Analysis

Table 2

Parameters obtained through tensile tests and used to describe the constitutive models for simulation.

Parameter (units)	Description	Values
		Austenite	Austenite + R-phase	R-phase
(MPa)	Elastic modulus before plateau	54,390	38,680	25,210
	Poisson’s ratio	0.33	0.33	0.33
(MPa)	Elastic modulus after plateau	22,510	18,970	19,700
(%)	Plateau’s strain	7	4.2	3.2
(MPa)	Stress at the plateau’s start	530	488	134
(MPa)	Stress at the plateau’s end	570	528	187
(°C)	Reference temperature	25	25	25
(MPa)	Maximum stress before plasticity	983	1,285	1,062