To echo the other answers, no, this should not void your warranty. There is a "Factory Seal" sticker on one of the screws on the bottom of the laptop, but the FTC has deemed that those stickers are an illegal practice and has begun fining companies for using them.
Unless you do obvious damage to the internal components, your warranty should remain intact. However, removing the CPU/GPU heatsink to apply new paste, for example, will void your warranty. I believe the limitations of the warranty prevent you from performing anything outside of routine upgrades (RAM, hard drives).