A bainite is a microstrucutre of steel consisting of needle-like particles of cementite embedded in a ferrite matrix.

To make 100% pearlite, the steel should be slowly cooled, while bainite and martensite are achieved through rapid cooling. Each microstructure has different heat treatment processes that must be followed to form. A combination of these processes can be used to achieve a mix of pearlite, bainite, and martensite in varying percentages based on the cooling rate and temperature control during heat treatment.

1) The nonequilibrium martensite does not appear on the diagram; and

2) The diagram provides no indication as to the time-temperature relationships for the formation of pearlite, bainite, and spheroidite, all of which are composed of the equilibrium ferrite and cementite phases.

Sword made of 1060 high carbon steel could be a good option. 1060 steel is quality but yet affordable steel. If you have a better budget you can pick spring steel or a tool steel like T10 or L6 bainite.

TRIP steel is Transformation Induced Plasticity steel. It is a composite steel that consists of ferrite, bainite, martensite precipitants and restrained austenite. The austenite will transform into martensite when strained, thus increasing the strength of the steel. To stabilize the austenite you need to introduce alloy elements, usually Manganese.