Ipc-7093a Pdf [verified] 〈2027〉

Z-axis expansion (CTE) differs between the rigid and flex sections. The guide helps assemblers predict how the board will behave during solder reflow, ensuring vias don't crack and components stay secure.

As IPC standards are proprietary and copyrighted, you can obtain the official PDF or hard copy through authorized retailers: IPC-7093A - Global Electronics Association ipc-7093a pdf