Tablet data on a mobile phone

[90miles]

Good morning everyone, I don't currently live in the U.S but do travel often (almost every two weeks) to the country, normally the expenses are paid for by the company which is why I don't even look at phone bills (wander how much they spend on data roaming), long story short, I'll be taking the California Zephyr in January and look forward to buying an iPhone, if I took an AT&T sim card off an iPad and threw it in the iPhone would I have the data ?