Thermal embrittlement caused by phase transformation in the temperature range of 204°C - 538°C limits the service temperature of duplex stainless steels. The rate of embrittlement varies markedly among commercial alloys. Specifically, alloys with high concentrations of Cr, Ni, Mn, and Mo are thought to demonstrate an enhanced rate of thermal embrittlement. The present study investigates a set of standard and lean grade wrought (2003, 2101, and 2205) and weld (2209 and 2101) alloys in order to better understand how alloying elements affect thermal embrittlement. Samples were aged between 260°C and 427°C for up to 10,000 hours and the embrittlement was assessed via microhardness and Charpy impact testing. Furthermore, the microstructure was characterized by scanning electron microscopy, transmission electron microscopy, and atom probe tomography. The results show complex relationships between segregation of Cr, Mn, and Si, G-phase precipitation, hardness of the ferrite, and impact toughness.