Are they made using the same processes, or is tempered steel made without the quenching process?
No. Not quite. The term 'Hardened steel' is often used to refer to 'Heat treated steel'. There are two separate steps in heat treatment. First the red hot steel is 'quenched' (rapidly cooled). This yields maximum hardness ,but the steel may be too brittle for the intended purpose. The next stage, 'tempering' is heating to a limited temperature, and slow cooling. This reduces the hardness somewhat, depending on the re-heat temperature, but restores some of the toughness lost in the first stage.
Hardening is the preliminary process. The fully hardened state may be far too brittle for practical use. The tempering process is tailored to reduce the actual hardness, to introduce more flexible alloys. The tempering method employed may be done at relatively low temperatures, but some alloys require prolonged soaking at elevated temperatures. Some may be cooled in air, but others may require quenching to end the process.
