열처리공학

1장 철강재료

1.1 철의 역사 ····································································································· 1
1.1.1 세계의 제철역사 ·················································································· 2
1.1.2 한국의 제철역사 ·················································································· 7
1.2 철강의 분류 ·································································································· 9
1.2.1 철의 성분별 분류 ················································································ 9
1.2.2 철의 형상별 분류 ·············································································· 16
1.3 철강의 원료 ································································································ 18
1.3.1 재선원료 ····························································································· 18
1.3.2 재강원료 ····························································································· 20
1.4 철강의 제조공정 ························································································ 26
1.4.1 제선공정 ····························································································· 26
1.4.2 제강공정 ····························································································· 27
1.4.3 연속주조공정 ····················································································· 31
1.4.4 압연공정 ····························································································· 34
1.4.5 조관공정 ····························································································· 39
1.4.6 특수강제조공정 ·················································································· 40


2장 금속의 결정

2.1 금속의 결정구조와 종류 ··········································································· 45
2.1.1 금속의 결정구조 ················································································ 47
2.1.2 금속의 결정구조의 종류 ··································································· 50
2.1.3 금속결정의 격자결함 ········································································ 59
2.1.4 순철의 결정구조 ················································································ 65



2.1.5 합금의 결정구조 ················································································ 66
2.2 결정의 면과 방향 ······················································································ 70
2.2.1 결정질 재료의 규칙성 ······································································ 70
2.2.2 결정방향과 결정면 ············································································ 72


3장 상태도와 조직

3.1 재료상 평형론 ···························································································· 77
3.1.1 상변태 ································································································ 77
3.2 평형상태도 ·································································································· 81
3.2.1 고용체의 평형상태도 ········································································ 81
3.2.2 Fe-C 평형상태도 ··············································································· 82
3.2.3 철-탄소 평형상태도(Fe-Fe3C상태도) ················································ 87
3.2.4 강의 조직과 그성질 ·········································································· 93
3.2.5 강의 상태도와 합급원소의 영향 ···················································· 104


4장 강의 특성과 열처리

4.1 물리적 성질 ······························································································ 113
4.1.1 열팽창계수 ······················································································· 113
4.1.2 열전도도 ··························································································· 115
4.1.3 자성 ·································································································· 115
4.1.4 전기저항 ··························································································· 116
4.2 기계적 성질 ······························································································ 116
4.2.1 강도와 인성 ····················································································· 116
4.2.2 피로강도 ··························································································· 120
4.2.3 내마모성 ··························································································· 125
4.2.4 절삭성 ······························································································ 127
4.2.5 냉간가공성 ······················································································· 129
4.2.6 열간가공성 ······················································································· 131
4.2.7 용접성 ······························································································ 135
4.3 화학적 성질 ······························································································ 136
4.3.1 내식성 ······························································································ 136
4.3.2 내열성 ······························································································ 140



5장 열처리 설비와 운용

5.1 가열장치 ··································································································· 145
5.1.1 열원의 종류 ····················································································· 145
5.1.2 열원과 가열방식 ·············································································· 146
5.1.3 열처리로의 분류 ·············································································· 149
5.1.4 열처리로와 가열방식 ······································································ 150
5.2 냉각장치 ··································································································· 167
5.2.1 냉각제의 종류 ················································································· 167
5.2.2 냉각장치의 종류 ·············································································· 169
5.2.3 분위기 가스와 그 발생장치 ··························································· 171
5.2.4 온도측정과 온도의 제어법 ····························································· 183


6장 강의 일반 열처리 공정

6.1 열처리 목적과 분류 ················································································· 195
6.2 풀림(Annealing) ······················································································· 198
6.2.1 완전풀림 ··························································································· 198
6.2.2 항온풀림 ··························································································· 199
6.2.3 구상화 풀림 ····················································································· 200
6.2.4 확산풀림 ··························································································· 201
6.2.5 응력제거 풀림 ················································································· 202
6.2.6 연화풀림 ··························································································· 202
6.3 불림(Normalizing) ···················································································· 203
6.3.1 보통불림 ··························································································· 204
6.3.2 2단불림 ···························································································· 204
6.3.3 항온불림 ··························································································· 204
6.3.4 이중불림 ··························································································· 205
6.4 뜨임(Tempering) ······················································································ 205
6.4.1 저온뜨임 ························································································· 205
6.4.2 고온뜨임 ························································································· 206
6.4.3 뜨임취성 ························································································· 207
6.5 담금질(Quenching) ·················································································· 207
6.5.1 담금질의 일반적 열처리공정 ························································· 207
6.5.2 인상담금질 ······················································································· 212



6.5.3 항온열처리 ······················································································· 213
6.6 고용화 열처리 ···················································································· 217
6.6.1 오스테나이트계 스테인리스강 ························································ 217
6.6.2 고 망간(Mn)강 ················································································· 218
6.7 심냉처리(Sub-zero Treatment) ······························································· 219
6.7.1 심냉처리의 목적 ·············································································· 219
6.7.2 잔류 오스테나이트의 발생원인과 영향 ········································· 219
6.7.3 처리방법 및 처리시기 ···································································· 220
6.7.4 심냉처리 효과 ················································································· 220
6.8 주요기계 부품용 강의 열처리 ································································ 221
6.8.1 기계구조용 탄소강의 열처리 ························································· 221
6.8.2 기계구조용 합금강의 열처리 ························································· 223
6.8.3 스프링강의 열처리 ·········································································· 227
6.8.4 베어링강의 열처리 ·········································································· 228
6.8.5 내열강의 강도와 열처리 ································································· 230


7장 표면 열처리 공정

7.1 표면경화 열처리 개요와 종류 ································································ 231
7.2 침탄처리 ··································································································· 232
7.2.1 고체침탄법 ····················································································· 234
7.2.2 가스침탄법 ····················································································· 236
7.2.3 진공침탄법 ····················································································· 240
7.3 침탄질화처리(청화법) ·············································································· 245
7.4 질화처리 ···································································································247
7.4.1 질화처리의 분류 ·············································································· 249
7.4.2 가스질화 및 산질화처리 ································································· 249
7.4.3 염욕질화처리 ··················································································· 251
7.4.4 이온질화처리 ··················································································· 253
7.4.5 가스연질화처리 ················································································ 255
7.4.6 침유질화처리 ··················································································· 256
7.5 고주파 표면경화처리 ··············································································· 257
7.5.1 고주파 열처리공정 ·········································································· 258
7.5.2 고주파 열처리 냉각방법 ································································· 259



7.5.3 고주파 표면열처리의 특성 ····························································· 259
7.6 화염표면경화처리 ····················································································· 260
7.7 금속침투법 ································································································ 262
7.7.1 세라다이징(Sherdizing) ··································································· 263
7.7.2 크로마이징(Chromizing) ································································· 263
7.7.3 칼로라이징(Calorizing) ···································································· 263
7.7.4 브로나이징(Boronizing) ·································································· 263
7.7.5 실리코나이징(Siliconizing) ······························································ 264
7.8 전자빔 표면경화처리 ··············································································· 264
7.9 레이져 표면경화처리 ··············································································· 265


8장 기타열처리

8.1 조질열처리 ······························································································ 267
8.1.1 조질열처리 과정 ·············································································· 267
8.1.2 조질열처리 요인 ·············································································· 270
8.2 진공열처리 ································································································ 272
8.2.1 진공열처리 과정 ·············································································· 273
8.2.2 냉각방법 ··························································································· 273
8.2.3 진공열처리의 특징 ·········································································· 274
8.3 증착법 ······································································································· 275
8.3.1 화학증착법 ······················································································· 275
8.3.2 물리증착법 ······················································································· 277
8.3.3 원자층 증착법 ················································································· 280
8.3.4 증착법 비교 ····················································································· 280
8.4 PLASMA 열처리 ······················································································· 282
8.4.1 플라즈마 질화법 ·············································································· 282
8.4.2 플라즈마 침탄법 ·············································································· 283
8.4.3 브로나이징(Boronizing) ·································································· 284
8.5 금속피막처리 ···························································································· 286
8.5.1 인산연 피막처리 ·············································································· 286
8.5.2 산화 피막처리 ················································································· 288
8.5.3 양극화 피막처리 ·············································································· 289



9장 비철금속의 열처리

9.1 알루미늄 합금의 열처리 ·········································································293
9.1.1 알루미늄 합금의 열처 개요와 분류 ·············································· 293
9.1.2 가공용 알루미늄 합금의 열처리 조건 ·········································· 295
9.1.3 주물용 알루미늄 합금의 열처리 조건 ·········································· 297
9.1.4 주물용 알루미늄 합금의 열처리 종류 ·········································· 298
9.1.5 알루미늄 합금의 열처리 변형과 대책 ·········································· 300
9.2 구리합금의 열처리 ··················································································· 307
9.2.1 균질화 처리 ····················································································· 307
9.2.2 어닐링 ······························································································ 309
9.2.3 응력제거처리 ··················································································· 312
9.2.4 강화처리 ··························································································· 314
9.3 티타늄과 티타늄합금 열처리 ·································································· 320
9.3.1 응력제거처리 ··················································································· 321
9.3.2 어닐링처리 ······················································································· 322
9.3.3 용체화처리와 시효처리 ··································································· 325
9.3.4 후처리 ······························································································ 330
9.4 니켈과 니켈합금 열처리 ········································································· 331
9.4.1 Ni-Cu 합금의 열처리 ······································································ 331
9.4.2 Ni-Cr 합금의 열처리 ······································································· 332
9.4.3 Ni-Fe 합금의 열처리 ······································································· 337
9.5 Mg 합금의 열처리 ··················································································· 338
9.5.1 Mg 합금의 열처리 종류 ································································· 338
9.5.2 열처리에 영향을 미치는 인자들 ···················································· 345
9.5.3 열처리 시 나타나는 문제점과 대책 ·············································· 346
9.5.4 용접 보수된 주조품의 열처리 ·························································348


10장 열처리 결함과 대책

10.1 소재 및 열처리전 가공 원인의 결함과 대책 ······································ 351
10.1.1 대형 비금속 개재물 ······································································ 351
10.1.2 편석 ································································································ 352
10.1.3 열간 가공 시 발생하는 결함 ······················································· 353



10.2 열처리 과정에서 나타나는 결함과 대책 ············································· 354
10.2.1 가열에 수반되는 결함 ··································································· 354
10.2.2 쾐칭.템퍼링에 수반되는 결함 ······················································ 358
10.2.3 고주파 경화처리에 수반되는 결함 ············································ 364
10.2.4 침탄경화에 수반되는 결함 ··························································· 367
10.2.5 열처리 경도불량과 변형방지의 요점 ·········································· 376


11장 열처리 부품의 시험 및 검사

11.1 경도시험 ································································································· 379
11.1.1 열처리와 경도시험의 중요성 ······················································· 379
11.1.2 브리넬 경도시험 ············································································ 380
11.1.3 로크웰 경도시험 ············································································ 385
11.1.4 쇼어 경도시험 ··············································································· 392
11.1.5 비커스 경도시험 ············································································ 394
11.2 기계적 시험 ···························································································· 404
11.2.1 인장시험 ························································································· 404
11.2.2 충격시험 ························································································· 410
11.2.3 굽힘시험 ························································································· 413
11.2.4 비틀림시험 ····················································································· 415
11.2.5 압축시험 ························································································· 416
11.2.6 파괴 인성 시험 ·············································································· 416
11.2.7 그리프시험 ····················································································· 416
11.3 조직시험 ································································································· 418
11.3.1 Macro 조직시험 ············································································· 418
11.3.2 Micro 조직시험 ············································································· 419
11.3.3 경화층 깊이시험 ············································································ 423
11.3.4 탈탄층 깊이시험 ············································································ 426
11.4 물리적 시험 ···························································································· 428
11.4.1 특성 X선 ························································································ 429
11.4.2 EPMA ······························································································ 430
11.4.3 전자현미경 ····················································································· 431
11.4.4 X선 회절 ························································································ 432
11.4.5 잔류응력 측정 방법 ······································································ 433



11.5 비파괴 검사 ···························································································· 434
11.5.1 침투탐상시험 ················································································· 434
11.5.2 자분탐상시험 ················································································· 435
11.6 강철의 불꽃시험 ···················································································· 436
11.6.1 불꽃시험의 기구 ············································································ 437
11.6.2 시험방법 ························································································· 437
11.6.3 강종의 추정방법 ············································································ 438
11.6.4 합금원소에 의한 불꽃의 특징 ······················································ 439



부록 1 ··············································································································· 442 부록 2 ··············································································································· 459 참고문헌 ··········································································································· 473