Answer
SAE 1070 carbon karfe ne ma'auni na gaba ɗaya-manufa riƙe zobba saboda da babban carbon abun ciki da kuma kudin-tasiri, samar da wani yawan amfanin ƙasa ƙarfi a kusa da $160$-$200$ ksi bayan man quenching da tempering. Duk da haka, SAE 1070 ya zama mai gatsewa a yanayin zafi na cryogenic kuma yana rasa ƙarfi da sauri sama da $250 ^{\circ}F$. Sabanin haka, Inconel X-750 (AMS 5699) wani nau'in nickel-chromium ne wanda ke dawwama a yanayin zafi ƙasa da $-300^{\circ}F$ kuma yana kiyaye amincin injina har zuwa $1300^{\circ}F$. Inconel X-750's hazo taurin ya ƙunshi samuwar $\gamma'$ lokaci ($Ni_3(Al, Ti)$), wanda ke ba da kyakkyawan ƙarfi-karye. Don aikace-aikacen teku ko sararin samaniya inda lalata da matsanancin zafin jiki suka zo daidai, Inconel X-750 shine zaɓi na tilas duk da ƙimar kuɗin da ake samu akan ƙarfe na carbon.
