What idioms are there about iron characters?

Idioms about iron-blooded figures are:

Kingoma iron,

A heart of stone,

Cycas bloomed,

Firmly,

Grinding needle with iron pestle,

Grinding the iron pestle into a needle,

Unscrupulous,

Stepped on iron shoes,

Danshu iron coupon,

Iron-bone collision,

Hate iron not to produce,

Scrap copper and iron,

Iron wall,

Strike while the iron is hot,

The iron pestle is ground into a needle,

Unarmed,

Iron lacquer silver hook,

Iron bars are ground into needles,

Irrefutable evidence,

Turn iron into gold,

Cut iron like mud,

Dan Shu fighters,

Steel bar,

Heart is like stone,

Nail,

Selling iron in a pan,

Collision in iron,

Iron plate copper pa,

Copper-headed iron arm,

Work hard and speed up.

Copper, steel and iron,

Iron net coral,

Jinge armored,

Wear out the iron inkstone,

The body of steel,

Monolithic,

Cycas bloomed,

Iron-walled copper mountain,

Iron-billed Kouga,

Jinge Tiema,

Iron core stone intestine,

Tang Chi Tiecheng,

Copper head and iron forehead,

Iron boxes are like mountains,

Guo tie Jin cheng,

Kill with an inch of iron,

Tough advice,

Steel castings,

Cast copper while the iron is hot,

Chewing iron mouth gold,

Copper-walled iron horse,

Cold-faced iron,

Iron ring,

Silver mountain iron wall,

Iron drum,

Copper cast iron castings,

Iron-faced spear teeth,

Cycas bloomed,

Copper heart and iron gallbladder,

Heroic singing voice