Ng\u01b0\u1eddi v\u00e0 \u0111\u1ed9ng v\u1eadt \u0111\u1ec1u c\u00f3 kh\u1ea3 n\u0103ng ghi nh\u1edb nh\u1ea5t \u0111\u1ecbnh, li\u1ec7u v\u1edbi c\u00e1c kim lo\u1ea1i v\u00f4 tri, v\u00f4 gi\u00e1c l\u1ea1i c\u00f3 kh\u1ea3 n\u0103ng ghi nh\u1edb kh\u00f4ng?<\/p>\n\n\n\n
V\u00e0o n\u0103m 1961, \u1edf M\u1ef9 c\u00f3 m\u1ed9t nh\u00e2n vi\u00ean k\u1ef9 thu\u1eadt \u0111\u00e3 l\u1ea5y t\u1eeb kho m\u1ed9t cu\u1ed9n d\u00e2y h\u1ee3p kim niken – titan, anh ta u\u1ed1n th\u1eb3ng s\u1ee3i d\u00e2y th\u00e0nh m\u1ed9t thanh th\u1eb3ng, sau \u0111\u00f3 \u0111em \u0111\u1eb7t thanh niken – titan g\u1ea7n m\u1ed9t l\u00f2 l\u1eeda, anh ta ph\u00e1t hi\u1ec7n m\u1ed9t s\u1ef1 k\u1ef3 l\u1ea1: s\u1ee3i d\u00e2y kim lo\u1ea1i l\u1ea1i l\u1ea5y tr\u1edf l\u1ea1i d\u1ea1ng cong nh\u01b0 c\u0169, nh\u01b0 th\u1ec3 \u1edf d\u00e2y kim lo\u1ea1i c\u00f3 “tr\u00ed nh\u1edb” v\u1eady. Anh c\u00e1n b\u1ed9 k\u1ef9 thu\u1eadt h\u1ebft s\u1ee9c th\u00fa v\u1ecb v\u1ec1 ph\u00e1t hi\u1ec7n c\u1ee7a m\u00ecnh. Anh ta l\u1eb7p l\u1ea1i th\u00ed nghi\u1ec7m nhi\u1ec1u l\u1ea7n v\u00e0 \u0111\u1ec1u nh\u1eadn \u0111\u01b0\u1ee3c k\u1ebft qu\u1ea3 nh\u01b0 nhau. Sau n\u00e0y ng\u01b0\u1eddi ta c\u00f2n ph\u00e1t hi\u1ec7n \u0111\u01b0\u1ee3c nhi\u1ec1u h\u1ee3p kim kh\u00e1c c\u0169ng c\u00f3 “tr\u00ed nh\u1edb”, v\u00ed d\u1ee5 h\u1ee3p kim c\u1ee7a ca\u0111imi, h\u1ee3p kim c\u1ee7a \u0111\u1ed3ng, nh\u00f4m, niken.<\/p>\n\n\n\n
V\u00ec sao c\u00e1c h\u1ee3p kim n\u00e0y l\u1ea1i c\u00f3 “kh\u1ea3 n\u0103ng nh\u1edb” nh\u01b0 v\u1eady? Khi nghi\u00ean c\u1ee9u k\u1ef9 h\u01a1n ng\u01b0\u1eddi ta t\u00ecm th\u1ea5y kh\u1ea3 n\u0103ng “ghi nh\u1edb” c\u1ee7a h\u1ee3p kim c\u00f3 li\u00ean quan \u0111\u1ebfn c\u1ea5u t\u1ea1o n\u1ed9i t\u1ea1i c\u1ee7a h\u1ee3p kim. N\u00f3i chung \u1edf c\u00e1c \u0111i\u1ec1u ki\u1ec7n kh\u00e1c nhau, c\u00e1c ch\u1ea5t \u1edf tr\u1ea1ng th\u00e1i tinh th\u1ec3 s\u1ebd c\u00f3 c\u1ea5u tr\u00fac c\u00f3 t\u00ednh \u1ed5n \u0111\u1ecbnh kh\u00e1c nhau. \u1ede nhi\u1ec7t \u0111\u1ed9 t\u01b0\u01a1ng \u0111\u1ed1i th\u1ea5p, c\u00e1c tinh th\u1ec3 c\u1ee7a h\u1ee3p kim c\u00f3 c\u1ea5u tr\u00fac kh\u00f4ng \u1ed5n \u0111\u1ecbnh. Khi t\u0103ng nhi\u1ec7t \u0111\u1ed9 qu\u00e1 m\u1ed9t nhi\u1ec7t \u0111\u1ed9 x\u00e1c \u0111\u1ecbnh n\u00e0o \u0111\u00f3, tinh th\u1ec3 s\u1ebd bi\u1ebfn th\u00e0nh d\u1ea1ng c\u1ea5u tr\u00fac \u1ed5n \u0111\u1ecbnh, nhi\u1ec7t \u0111\u1ed9 n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 nhi\u1ec7t \u0111\u1ed9 chuy\u1ec3n bi\u1ebfn c\u1ea5u tr\u00fac. \u0110\u00f3 l\u00e0 l\u00fd do t\u1ea1i sao s\u1ee3i h\u1ee3p kim niken – titan l\u1ea1i l\u1ea5y l\u1ea1i d\u1ea1ng cong ban \u0111\u1ea7u khi t\u0103ng nhi\u1ec7t \u0111\u1ed9. V\u1edbi s\u1ee3i h\u1ee3p kim niken – titan, n\u1ebfu \u0111em ch\u1ebf t\u1ea1o th\u00e0nh h\u00ecnh d\u00e1ng x\u00e1c \u0111\u1ecbnh, sau \u0111\u00f3 t\u0103ng nhi\u1ec7t \u0111\u1ed9 \u0111\u1ebfn 150\u00b0C r\u1ed3i l\u1ea1i l\u00e0m l\u1ea1nh, d\u00f9ng ngo\u1ea1i l\u1ef1c thay \u0111\u1ed5i h\u00ecnh d\u1ea1ng c\u1ee7a s\u1ee3i d\u00e2y, l\u00fac n\u00e0y s\u1ee3i d\u00e2y \u0111ang \u1edf tr\u1ea1ng th\u00e1i c\u00f3 c\u1ea5u tr\u00fac tinh th\u1ec3 kh\u00f4ng \u1ed5n \u0111\u1ecbnh. B\u00e2y gi\u1edd n\u1ebfu \u0111em gia nhi\u1ec7t s\u1ee3i d\u00e2y \u0111\u1ebfn nhi\u1ec7t \u0111\u1ed9 chuy\u1ec3n bi\u1ebfn c\u1ea5u tr\u00fac (95\u00b0C) tr\u1edf l\u00ean, h\u1ee3p kim niken – titan l\u1ea1i ph\u1ee5c h\u1ed3i tr\u1ea1ng th\u00e1i \u1ed5n \u0111\u1ecbnh ban \u0111\u1ea7u. \u0110i\u1ec1u \u0111\u00f3 t\u01b0\u01a1ng t\u1ef1 nh\u01b0 l\u00e0 h\u1ee3p kim niken – titan c\u00f3 tr\u00ed nh\u1edb v\u00e0 \u0111\u00e3 ph\u1ee5c h\u1ed3i \u0111\u01b0\u1ee3c h\u00ecnh d\u1ea1ng ban \u0111\u1ea7u. C\u00e1c nh\u00e0 khoa h\u1ecdc g\u1ecdi \u0111\u00f3 l\u00e0 hi\u1ec7u \u1ee9ng ghi nh\u1edb h\u00ecnh d\u1ea1ng.<\/p>\n\n\n\n
Ng\u00e0y nay hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y \u0111\u00e3 \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng v\u00e0o m\u1ee5c \u0111\u00edch nghi\u00ean c\u1ee9u khoa h\u1ecdc trong c\u00f4ng t\u00e1c th\u00e1m kh\u00f4ng. V\u00ed d\u1ee5 \u0111\u1ec3 thu th\u1eadp c\u00e1c s\u1ed1 li\u1ec7u v\u1ec1 M\u1eb7t Tr\u0103ng c\u1ea7n ph\u1ea3i ph\u1ea3n h\u1ed3i c\u00e1c t\u01b0 li\u1ec7u t\u1eeb M\u1eb7t Tr\u0103ng v\u1ec1 Tr\u00e1i \u0110\u1ea5t. Mu\u1ed1n th\u1ebf ph\u1ea3i \u0111\u1eb7t tr\u00ean M\u1eb7t Tr\u0103ng m\u1ed9t anten c\u00f3 d\u1ea1ng nh\u01b0 m\u1ed9t c\u00e1i \u00f4 l\u1edbn (anten parabon). L\u00e0m th\u1ebf n\u00e0o \u0111\u01b0a \u0111\u01b0\u1ee3c m\u1ed9t c\u00e1i \u00f4 l\u1edbn nh\u01b0 v\u1eady l\u00ean M\u1eb7t Tr\u0103ng? C\u00e1c nh\u00e0 khoa h\u1ecdc ngh\u0129 \u0111\u1ebfn nguy\u00ean l\u00fd d\u01b0\u01a1ng \u00f4 d\u1ef1a v\u00e0o c\u00e1c h\u1ee3p kim “c\u00f3 tr\u00ed nh\u1edb”. Tr\u01b0\u1edbc h\u1ebft ng\u01b0\u1eddi ta ch\u1ebf t\u1ea1o m\u1ed9t c\u00e1i \u00f4 l\u1edbn \u1edf nhi\u1ec7t \u0111\u1ed9 cao h\u01a1n 40\u00b0C. Sau \u0111\u00f3 g\u1ea5p c\u00e1i \u00f4 n\u00e0y th\u00e0nh m\u1ed9t h\u00ecnh d\u1ea1ng chi\u1ebfm m\u1ed9t th\u1ec3 t\u00edch b\u00e9 \u0111\u1ec3 c\u00f3 th\u1ec3 cho v\u00e0o con t\u00e0u v\u0169 tr\u1ee5 v\u00e0 ph\u00f3ng l\u00ean M\u1eb7t Tr\u0103ng. Khi anten \u0111\u00e3 l\u00ean \u0111\u1ebfn M\u1eb7t Tr\u0103ng, bao \u0111\u1ef1ng \u00f4 m\u1edf ra, c\u00e1c s\u1ee3i d\u00e2y h\u1ee3p kim s\u1ebd cao h\u01a1n 95\u00b0C v\u00e0 anten s\u1ebd ph\u1ee5c h\u1ed3i nguy\u00ean tr\u1ea1ng h\u00ecnh parabon v\u1ed1n c\u00f3 tr\u01b0\u1edbc \u0111\u00f3. \u0110\u00f3 qu\u1ea3 l\u00e0 \u0111i\u1ec1u h\u1ebft s\u1ee9c k\u1ef3 di\u1ec7u.<\/p>\n\n\n\n
H\u1ee3p kim c\u00f3 tr\u00ed nh\u1edb ng\u00e0y c\u00e0ng \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng r\u1ed9ng r\u00e3i h\u01a1n. C\u00e1c h\u1ec7 th\u1ed1ng truy\u1ec1n d\u1eabn \u00e1p l\u1ef1c tr\u00ean m\u00e1y bay tr\u01b0\u1edbc \u0111\u00e2y hay c\u00f3 hi\u1ec7n t\u01b0\u1ee3ng r\u00f2 r\u1ec9 d\u1ea7u g\u00e2y s\u1ef1 c\u1ed1 \u1edf c\u00e1c \u0111\u1ea7u ti\u1ebfp n\u1ed1i c\u1ee7a c\u00e1c \u1ed1ng d\u1eabn, g\u00e2y \u1ea3nh h\u01b0\u1edfng x\u1ea5u \u0111\u1ebfn vi\u1ec7c \u0111i\u1ec1u khi\u1ec3n m\u00e1y bay. Ng\u01b0\u1eddi ta \u0111\u00e3 d\u00f9ng h\u1ee3p kim c\u00f3 tr\u00ed nh\u1edb ch\u1ebf t\u1ea1o c\u00e1c \u0111\u1ea7u n\u1ed1i c\u00e1c \u1ed1ng d\u1eabn, kh\u00f4ng ch\u1ec9 r\u1ea5t b\u1ec1n m\u00e0 c\u00f2n kh\u00f4ng s\u1ee3 b\u1ecb va \u0111\u1eadp g\u00e2y bi\u1ebfn d\u1ea1ng. Khi c\u1ea7n ph\u1ee5c h\u1ed3i tr\u1ea1ng th\u00e1i ban \u0111\u1ea7u ch\u1ec9 c\u1ea7n gia nhi\u1ec7t ch\u00fat \u00edt l\u00e0 c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c d\u1ec5 d\u00e0ng. Khi d\u00f9ng h\u1ee3p kim c\u00f3 tr\u00ed nh\u1edb \u0111\u1ec3 ch\u1ebf t\u1ea1o c\u00e1c \u0111\u1ea7u n\u1ed1i s\u1ebd tr\u00e1nh \u0111\u01b0\u1ee3c hi\u1ec7n t\u01b0\u1ee3ng r\u00f2 r\u1ec9, tr\u00e1nh \u0111\u01b0\u1ee3c nhi\u1ec1u s\u1ef1 c\u1ed1 \u0111\u00e1ng ti\u1ebfc. Theo th\u1ed1ng k\u00ea, tr\u00ean \u1ed1ng phun kh\u00ed c\u1ee7a m\u1ed9t m\u00e1y bay chi\u1ebfn \u0111\u1ea5u c\u00f3 \u0111\u1ebfn h\u00e0ng tr\u0103m ngh\u00ecn \u0111\u1ea7u \u1ed1ng n\u1ed1i.<\/p>\n\n\n\n
Ng\u01b0\u1eddi ta c\u0169ng s\u1eed d\u1ee5ng h\u1ee3p kim c\u00f3 tr\u00ed nh\u1edb \u0111\u1ec3 ch\u1ebf t\u1ea1o \u0111inh t\u00e1n. Tr\u01b0\u1edbc khi s\u1eed d\u1ee5ng \u0111inh t\u00e1n ng\u01b0\u1eddi ta gia c\u00f4ng \u0111\u1ea7u to c\u1ee7a \u0111inh t\u00e1n th\u00e0nh h\u00ecnh tr\u1ee5 thon nh\u01b0 nhau, sau \u0111\u00f3 ng\u01b0\u1eddi ta cho \u0111inh v\u00e0o l\u1ed7 trong \u0111i\u1ec1u ki\u1ec7n nhi\u1ec7t \u0111\u1ed9 th\u1ea5p. Khi t\u0103ng cao nh\u1eb9 nhi\u1ec7t \u0111\u1ed9, \u0111\u1ea7u \u0111inh t\u00e1n l\u1ea1i n\u1edf to nh\u01b0 c\u0169 v\u00e0 \u0111\u01b0\u1ee3c gi\u1eef ch\u1eb7t v\u00e0o l\u1ed7.<\/p>\n\n\n\n
T\u1eeb kho\u00e1: H\u1ee3p kim c\u00f3 tr\u00ed nh\u1edb; S\u1ef1 h\u1ed3i ph\u1ee5c h\u00ecnh d\u1ea1ng.<\/p>\n\n\n\n
<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"
Ng\u01b0\u1eddi v\u00e0 \u0111\u1ed9ng v\u1eadt \u0111\u1ec1u c\u00f3 kh\u1ea3 n\u0103ng ghi nh\u1edb nh\u1ea5t \u0111\u1ecbnh, li\u1ec7u v\u1edbi c\u00e1c kim lo\u1ea1i v\u00f4 tri, v\u00f4 gi\u00e1c l\u1ea1i c\u00f3 kh\u1ea3 n\u0103ng ghi nh\u1edb kh\u00f4ng? V\u00e0o n\u0103m 1961, \u1edf M\u1ef9 c\u00f3 m\u1ed9t nh\u00e2n vi\u00ean k\u1ef9 thu\u1eadt \u0111\u00e3 l\u1ea5y t\u1eeb kho m\u1ed9t cu\u1ed9n d\u00e2y h\u1ee3p kim niken – titan, anh ta u\u1ed1n th\u1eb3ng […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[8,15],"tags":[],"class_list":["post-7815","post","type-post","status-publish","format-standard","hentry","category-hoa-hoc","category-hoi-dap-khoa-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/7815","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=7815"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/7815\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=7815"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=7815"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=7815"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}