The Iron Way in Chinese / Japanese...

鉄心石腸 is a Japanese proverb that suggests you should have the inner-strength and will as hard and steadfast as iron.

It's the Japanese way of saying, “stay strong.” This is an especially uplifting thing to say to a person in distress or recovering from a disaster. It's kind of the survivor's creed.

If you literally translate this, it means “iron will, stone guts” or “iron heart, rock-hard bowels.”

鐵拳 is a common theme used by various schools of martial arts.

鐵 means “iron” but, in some cases, can mean “indisputable.”
拳 means fist.

Some schools use the older/Taiwanese way to Romanize the iron fist, so you may have seen it spelled “Tieh Chuan” instead of “Tie Quan.” Neither way is technically incorrect.

Note that in Mandarin, the first part of the first character sounds like the English word “tea,” blending into a soft “-eh” sound. The second character sounds a lot like “chew on” but as if it is one syllable.

After WWII in Japan, the Kanji for iron was simplified. This new Kanji form is shown to the right. If you want this modern Japanese version, please click on the Kanji to the right, instead of the button above. The characters shown to the left would still be considered the old or ancient Japanese version of this title.

百折不屈 is a Korean proverb that means “indomitable spirit,” at least, that is the way it is commonly translated in martial arts circles (Taekwondo, Hapkido, etc.).

The literal translation is “[one] hundred [times] broken [still] don't succumb.”
Or more naturally translated, “Even if attacked/beaten one hundred times, still be undaunted/indomitable.”

Notes:
Some will say this is one long word rather than a proverb.
This is also a proverb/word in Chinese though rarely used in modern times.