Compression behavior of nanocrystalline TiN

•No phase transition was observed during compression for each sample.•A fit of the pressure (P) versus volume data to a second Birch–Murnaghan equation yielded the following parameters for 16 nm, 34 nm and 80 nm, zero-pressure volume, V0=75.77 Å3, 75.98 Å3 and 76.06 Å3, bulk modulus, B0=320(7) GPa, 338(6) GPa and 287(3) GPa, respectively.•The P–V data of 16 nm is relatively discrete at P>20 GPa compared with those of 34 nm, 80 nm and previous works.•The full width at half maximum of 16 nm continues to increase, whereas those of 34 nm and 80 nm become almost constant when the pressure reaches a certain value.

We have investigated the size-dependent high pressure behavior of nanocrystalline TiN using an angle-dispersive X-ray diffraction technique in a diamond-anvil cell at room temperature. No phase transition was observed during compression for each sample. A fit of the pressure versus volume data to a second Birch–Murnaghan equation yielded the following parameters for 16 nm, 34 nm and 80 nm, zero-pressure volume, V0=75.77 Å3, 75.98 Å3 and 76.06 Å3, bulk modulus, B0=320(7) GPa, 338(6) GPa and 287(3) GPa, respectively. This result along with a reanalysis of previous studies on TiN indicates that the bulk modulus first increases and then decreases with decreasing grain size. The compressibility of TiN has a minimum at ~34 nm.