SS will average your top earning 30 years, so working for only 10 means you will have 20 zeros in your average.
It's not as bad as it sounds, though, as SS is designed to replace a higher percentage of lower incomes. So your benefit for 10 years of work is more than one third the benefit of 30 years of work at equivalent salary.
There is a calculator on the ssa.gov website that lets you specify an arbitrary stop-work date and your salary between now and then, and estimates your benefit at retirement age based on those partial earnings. Very handy.
Go here:
http://www.ssa.gov/estimator/ click on "Estimate Your Retirement Benefits"
enter your info so they can pull your record.
it will estimate your benefits at ages 62, 67, and 70 assuming you work until that age. Ignore those.
Click on "Add a New Estimate" and tell it what age you intend to stop working and how much you will make on average between now and then.
It will tell you your new estimated benefit amount if you stop working then, but only at age 62.
You're welcome.