Blockchain utilizes cryptography as a means of protecting the identities of users, ensuring transactions are done safely and securing all information and storages of value. Therefore, anyone using blockchain can have complete confidence that once something is recorded on a blockchain, it is done so legitimately and in a manner that preserves security.
The type of cryptography used in blockchain is public-key cryptography. Public-key cryptography, also known as asymmetric cryptography. A combination of a users public key and private encrypt the information, whereas the recipients private key and sender’s public key decrypt it. It is impossible to work out what the private key is based on the public key. Therefore, a user can send their public key to anyone without worrying that someone will gain access to their private key. The sender can encrypt files that they can be sure will only be decrypted by the intended party.
Therefore Blockchains do use encryption as part of its cryptography. You can have a look article below for more information about blockchain.