Flow forming is a cold forming process used for the production of dimensionally accurate near net shaped hollow components used in various fields of industry. Due to the nature of the process, generation of residual stresses are inevitable. The objective of this study is to investigate the generation and distribution of residual stresses in flow formed components, to understand the evolution of stresses during the process. During flow forming process several catastrophic failures have been observed to occur that are believed to be related to the progress of residual stresses. The aim of this study is to monitor the progress of residual stress in components after different levels of deformation by flow forming. Due to the nature of martensitic steel, the microstructure might undergo strain induced phase transformation under high plastic deformation, which will be explored in this study.