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In this work, a cross-laboratory comparison is conducted to critically examine experimental techniques within the High-Strain Rate Mechanics of Materials Laboratory at the University of Utah and the Experimental Solid Mechanics Department at Sandia National Laboratories. The study is aimed at identifying, quantifying, and reducing sources of uncertainty in reported Taylor–Quinney coefficients. Vacuum arc remelted 304L stainless steel specimens extracted from the same ingot are tested in both laboratories under dynamic tension at nominal strain rates of \dot(epsilon) = 450^{-1} and \dot(epsilon) = 900 s^-1 . Independent experiments at both the University of Utah and Sandia National Laboratories report Taylor–Quinney coefficients of \beta_int = 0.85 and \beta_int = 0.9-1.0 for \dot(epsilon) = 450^{-1} and \dot(epsilon) = 900 s^-1, respectively. Sources of variation between labs and practices to mitigate these are also discussed. 

A study was conducted to investigate the temperature dependence of thermomechanical coupling in Inconel 718 (IN718). IN718 was selected as a model material due to deformation being predominantly accommodated by planar slip. Split-Hopkinson (or Kolsky) tension bar experiments were conducted at a nominal strain rate of 750 s^-1 at room temperature and 450 ^o C, representing homologous temperatures (T_H=T/T_melt) of T_H = 0.2 and T_H = 0.5, respectively. During deformation, specimen gauge sections were imaged with a high-speed infrared camera. Using one-dimensional wave analysis, the transient heat conduction equation, and temperature- dependent specific heat capacity values, the temperature rise as a function of plastic strain was used to calculate plastic work, thermal work, and the plastic work to heat conversion efficiency, commonly known as the Taylor–Quinney coefficient (TQC). As expected, a significant reduction in plastic work was observed during testing at elevated temperatures. The temperature rise due to plastic deformation was observed to be lower at room temperature compared to elevated temperature experiments. It is reported here for the first time that the TQC is a temperature-sensitive quantity. At T_H = 0.5, a nearly complete conversion of plastic work to heat was observed (TQC = 1.0). Under ambient conditions of T_H = 0.2, a much lower efficiency TQC = 0.4 was observed.