This paper presents an investigation into the thermal stability of microwave cavity resonators using several novel alloy materials. Shaped spherical resonators are additively manufactured by Selective Laser Melting (SLM) technology from alloy powders. The manufacturing parameters of each sample is presented, and their thermal stability is experimentally characterized by measuring the RF performance under different temperatures. The Ti64, Zr702 and TNTZ samples show much improved thermal stability as compared with the common aluminium alloy used for space application. A detailed comparison between different samples in terms of their mechanical, thermal and RF performance is presented. This work introduces an expanded range of materials that may be used for microwave filters and opens opportunity for new temperature compensation techniques for high power filters.