마이크로 펄스 플라즈마 질화법에 의한 선박엔진용 부품의 표면경화에 관한 연구

Abstract

본 연구는 마이크로 펄스 플라즈마 질화처리한 FCD60, S53C, SCM440강재를 고주파 유도경화 열처리한 동일 강재와의 비교분석을 통해 강 표면에 생성된 경화층의 두께와 경도 및 조직을 조사하고 마모시험을 행하였다.

Hv550의 유효경도를 갖는 경화깊이는 마이크로 펄스 플라즈마 질화의 경우 FCD60, S53C, SCM440에서 각각 30㎛,25㎛,25㎛이었고, 고주파 유도경화 열처리는 각각 1.4mm이었다.

경화층의 XRD분석결과 마이크로 펄스 플라즈마 질화의 경우 FCD60과 S53C는 주로 r'- Fe₄N, SCM440은 r' - Fe₄N과 ε- Fe₃N의 혼합상이 생성되었으며, 고주파 유더경화 열처리된 경화층은 α- Fe로 모재와 같았다.

또한, 마모시험결과 상온에서는 고주파 유도경화 열처리에 의해 생성된 경화층이 내마모성이 좋으나, 고온(150℃)과 윤활상태에서는 마이크로 펄스 플라즈마 질화처리하에 의하여 생성?? 질화층의 내마모성이 우수하였다.

The case hardening of FCD60, S53C and SCM440 by micro-pulse plasma nitriding and high frequency induction heat treatment was invesigated.

The effective case depth (of which hardeness is over Hv550) of FCD60, S53C and SCM440 nitrided by micro-;ulse plasma method was 30, 25 and 25㎛, respectively.

XRE analysis of nitrided layer, showed that mixture of r' - Fe₄N and ε- Fe₃N phases formed on SCM440, r' -Fe₄N single phase formed on S53C and FCD60.

In case of hihh frequency induction heat treatment, hardened layer was α - Fe single phase.

The hardened hayer formed by high frequency induction heat treatment was more resistant to wear than nitrided layer at room temperature, however nitrided layer by micro-pulse plasma nitriding was more resistant to wear than induction hardened layer at high temperature and lubricated condition.

The case hardening of FCD60, S53C and SCM440 by micro-pulse plasma nitriding and high frequency induction heat treatment was invesigated.

The effective case depth (of which hardeness is over Hv550) of FCD60, S53C and SCM440 nitrided by micro-;ulse plasma method was 30, 25 and 25㎛, respectively.

XRE analysis of nitrided layer, showed that mixture of r' - Fe₄N and ε- Fe₃N phases formed on SCM440, r' -Fe₄N single phase formed on S53C and FCD60.

In case of hihh frequency induction heat treatment, hardened layer was α - Fe single phase.

The hardened hayer formed by high frequency induction heat treatment was more resistant to wear than nitrided layer at room temperature, however nitrided layer by micro-pulse plasma nitriding was more resistant to wear than induction hardened layer at high temperature and lubricated condition.