You will receive a single refund, but it will be for the joint tax return (your refund is combined for both of you).
When you file jointly, you will add all of the information for both of you together on one form.
If you were filing separately, you would create two different tax returns, one for each of you, and there would be two separate checks if you both had refunds.
There are many advantages to using the Married Filing Jointly filing status:
https://ttlc.intuit.com/replies/3288477
