Reciting aloud while performing prayer

While performing a ritual prayer, does it invalidate our prayer if we recite aloud when we are to read silently or if we smile during the prayer?

What will happen if we quit the supplications that we have to read during the prayer?

It is necessary for an imam to recite al-Fatiha and additional verses loudly in the first two rak'ahs of fard prayers of fajr (morning), maghrib (evening) and isha (night) prayers. And it is also necessary for both the imam and the congregation and an individual who prays alone to read secretly in all prayers except Friday and eid prayers. The prayer does not become invalid if wajib parts are abandoned. If abandoning is because of forgetting, it is compensated with sajdah as-sahw. If it is done intentionally, it is a bad deed and one falls into sin. Yet, the prayer is still valid.

If one reads the verses so loud as one or two people around him can hear, this is not accepted as reading aloud, on the contrary, it is accepted as reading silently. Reciting loudly, for instance, according to Ibn Abidin, occurs when everybody in the first line of the congregation hears (Mehmet Zihni Efendi, 250). Or, it can be said that whispering is accepted as reading silently and reciting loudly is reading aloud. Smiling silently while praying does not make prayer invalid if lips do not move. If lips trembls and laughing occurs so loud as the person himself hears, the prayer becomes invalid. Laughing out loudly  invalidates both the prayer and ablution (wudu). If what is meant by supplications are al-Fatiha and and additional chapter or verses, one has to perform sajdah as-sahw when he skips them in order to complete the prayer. For, reading them are wajib. If Subhanaka, glorifications, Salli and Barik supplications and at-tahiyyat are meant, sajdah as-sahw is not necessary when they are skipped because it is sunnah to read them.