Bidirectional tensile testing cell for in situ small angle X-ray scattering investigations of soft tissue

An X-ray cell for the acquisition of one-dimensional mechanical force–displacement diagrams of soft tissue samples has been developed. The combination of X-ray and mechanical data allows new insights into the coupling of the macroscopic behavior and nanoscopic structural changes during the application of load. Two linear μ-translation stages are used to symmetrically – i.e. bidirectionally – stretch the sample. A video-extensometer is installed to record geometrical changes of the sample during measurement which allows to determine true stresses and strains. The sample can be immersed in a liquid and heated. We demonstrate the advantages over common unidirectional tensile testing devices without length measurement systems by comparing different mechanical and diffraction data sets of human arterial tissue.