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Aluminum nitride (AlN) and boron nitride (BN) are well‐known ceramic materials with numerous valuable properties, whereas recently there is a growing field of research on the AlN/BN advanced ceramic materials. Here, we present a study on boron‐rich AlN, structural and electronic properties, and structure–property relationship. Several AlxB1−xN solid solutions (x = 1, .875, .75, and .625) have been investigated, and structure optimization has been performed for four different structure types: h‐BN, wurtzite, sphalerite, and rock salt. First‐principles calculations were performed using hybrid B3LYP functional. New modifications and compounds have been predicted as a function of boron concentration in AlN, and especially, interesting phase transitions were found at extreme pressure conditions. Electronic properties and band structures were computed, and the possibility for bandgap tuning has been discovered. The present study, and especially the structure–property relationship, gives new possibilities for bandgap engineering in boron‐rich AlN electroceramic materials.

The incorporation of N into Ni [N] solid solution by gaseous nitriding in NH 3 -H 2 containing atmospheres, corresponding to a nitriding potential r N,0 at the tube furnace inlet, was studied at 450uC. For the encountered low N contents c N (,1 at.-%), validity of Henry's law is expected, i.e. proportionality of c N with the nitriding potential r N,0 of the gas inserted into the furnace. However, NH 3 decomposition in the furnace, even at the temperature considered, which is usually neglected, leads to deviation from this proportionality, i.e. an effective r N ,r N,0 operates. A scheme for obtaining the c N (r N ) data from the experimental c N (r N,0 ) data is described.