1. 소개
우리를 C90300 is a widely used tin-bronze casting alloy that delivers a practical combination of good castability, 부식 저항 (특히 해양 환경에서), bearing/wear behavior and satisfactory mechanical strength.
It is specified for bushings, 펌프 부품, 밸브, gears and other components where service loading, sliding contact and corrosion resistance are primary drivers.
2. What is Bronze UNS C90300?
UNS C90300 is a cast tin 청동 alloy in the UNS (통합 번호 매기기 시스템) 구리 합금 제품군.
It is formulated for foundry use and is widely specified where a balance of 주파수, 부식 저항 (particularly in marine and water-handling environments), good bearing/wear behavior and reasonable mechanical strength 필요합니다.
In practice C90300 is chosen for components such as bushings, 소매, pump and valve parts, small gears and marine fittings where sliding contact, embedability and resistance to seawater or wet corrosion are important.
Key features and metallurgical character
- 좋은 주파수. C90300 pours and fills molds predictably in sand, shell and investment processes, enabling reasonably thin sections and good surface detail when processed correctly.
- Tin-strengthened matrix. Tin acts as a substitutional alloying element in copper, raising hardness, wear resistance and strength relative to plain copper while preserving ductility sufficient for many bearing and structural uses.
- Bearing and tribological performance. 합금이 나타납니다 conformability and embedability—it will accept small contaminant particles into the softer bronze matrix rather than score a harder mating shaft, making it suitable for plain bearings and bushings under boundary or mixed lubrication.
- Excellent wet-environment corrosion resistance. Tin bronzes resist general corrosion and perform well in seawater and many industrial aqueous environments; they are less prone to dezincification or rapid localized attack than many brasses.
- Not precipitation-hardening. Mechanical properties are established primarily by composition and solidification/microstructure; C90300 is not normally subject to strengthening by solution/aging treatments.
Stress-relief or annealing operations are used mainly for dimensional stability or ductility adjustments. - 적당한 가공 가능성. Tin improves chip formation and machinability relative to many high-strength copper alloys; carbide tooling and standard bronze machining practices are appropriate for production work.
3. Alloy identity and typical chemistry
Values are presented as typical weight-percent ranges used for design and procurement; always confirm exact limits with the foundry’s mill/certified analysis for any critical application.
| 목 | 전형적인 구성 (wt%) | 기능 / 효과 |
| UNS designation | C90300 | Unified Numbering System identity for this cast tin-bronze. |
| 구리 (Cu) | 균형 (~86.0 – 89.0%) | 비금속; provides matrix, thermal/electrical properties and ductility. |
| 주석 (Sn) | 7.5 - 9.0% | Principal strengthening and wear/corrosion-resistant element in the alloy. |
| 아연 (Zn) | 3.0 - 5.0% | 유동성을 향상시킵니다, castability and deoxidation of the melt. |
| 니켈 (~ 안에) | 0 - 1.0% (타이핑.) | 선택 과목; can improve corrosion resistance, strength and toughness. |
| 철 (Fe) | ≤ ~0.5% (타이핑.) | Controlled impurity or deliberate addition; affects strength and wear. |
선두 (PB) |
≤ ~0.2–0.25% (추적하다) | May appear at trace levels in some castings; small amounts aid machinability but are not a defining element. |
| 규소 (그리고) | ≤ ~0.5% (추적하다) | Deoxidation/fluidity influence; normally controlled to low levels. |
| 인 (피) | ≤ ~0.03% (추적하다) | Deoxidizer/degasser residue; kept very low to avoid embrittlement. |
| 황 (에스) | ≤ ~0.02% (추적하다) | 불결; low levels tolerated; excessive S is detrimental. |
| 알류미늄 / 망간 / other | Each typically ≤ ~0.1–0.3% | Minor micro-alloying or tramp elements controlled to specification. |
4. Physical and mechanical properties
Below are representative as-cast values for C90300 drawn from typical supplier and material-data references.
Actual properties vary with casting process, 섹션 두께, gating strategy and melting practice — always validate with cast coupons from your foundry.
Physical properties
| 재산 | 일반적인 값 |
| 밀도 | ≈ 8.7–8.9 g/cm³ (≈ 0.318 lb/in³). |
| solidus / 액체 | ~854 °C (solidus) - ~1000 °C (액체) (guide to safe pouring and superheat). |
| 열전도율 | ~70–75 W/m·K (depends on Sn/Zn content). |
| 전기 전도성 | ~10–12 % IACS (low compared with pure copper). |
| 열 팽창 계수 | ≈ 17 × 10 ° /° C (room to moderate temps). |
기계적 특성 (typical as-cast)
| 재산 | 일반적인 범위 / 값 |
| 인장 강도 (uts) | ~300–320 MPa (≈ 44–46 ksi) |
| 생산하다 (0.5% 오프셋) | ~145–152 MPa (≈ 21–22 ksi) |
| 연장 (~에 50 mm) | ~18–30% depending on section and process |
| 브리넬 경도 (Bnn) | ~ 70 HB (주조된 전형적인) |
| 탄성 계수 | ~110–125 GPa |
5. Casting behavior and foundry practice
Suitable casting processes
C90300 is adaptable to the major casting methods used for bronzes:
- 모래 주조 — economical for large or heavy sections.
- 투자 캐스팅 (잃어버린 왁스 캐스팅) — best surface finish and dimensional accuracy for thinner, 상세한 부분.
- 쉘 성형 and permanent-mold casting — intermediate options offering improved surface finish and tolerance.
- Continuous and centrifugal casting are also used for bars, rings and certain shapes.
Critical casting parameters
- 쏟아지는 온도 / 과열 상태: respect the alloy liquidus and avoid excessive superheat;
Concast data indicate liquidus near ~1000 °C and solidus near ~854 °C — control within a narrow window to balance fluidity and avoid oxidation/dross. - 청결을 녹입니다: degassing and filtration are essential; tin bronzes are sensitive to hydrogen porosity and oxide inclusions — ceramic filters and rotary degassers reduce risks.
- 게이팅 & 급송: design feeders to supply shrinkage in heavy sections and use gradual sectional transitions to avoid hot-spots and hot-tears.
시뮬레이션 (fill/solidification) is recommended for complex geometries. - 응고 제어: directional solidification with chills or chills/risers helps reduce shrinkage defects and refines microstructure in thicker portions.
캐스팅 후 열처리
C90300 is not a precipitation-hardening alloy; it does not respond to solution-age heat treatments to raise strength.
Typical thermal steps are stress-relief anneals (to remove casting stresses and improve machinability) or moderate anneals to improve ductility where required.
Practical foundry practice relies on casting control — not heat treatment — for most mechanical property objectives.
6. 가공 가능성, 합류 & 마무리 손질
가공 가능성
- 적당한 가공 가능성 — tin content enhances chip formation and machinability relative to many high-strength copper alloys;
common machinability rating values place C90300 in a practical class for routine turning, milling and drilling with carbide tooling. - Recommended practice: use rigid fixturing, 카바이드 툴링 (coated grades for production), conservative feeds to avoid built-up edge, and light finishing passes for critical surfaces.
Sulfur and lead contents in other alloys (not C90300 lead-free variants) can alter chip control — verify composition before selecting cutting parameters.
합류
- 브레이징 is the preferred joining method for bronze castings when required (filler metals and flux selected for bronze compatibility).
- 용접 is generally avoided for large castings because bronze tends to suffer from thermal cracking and property changes; localized welding can be used with specialist procedures and post-weld stress relief where unavoidable.
표면 마감
- 세련, 도금 (~ 안에, Ag), lacquering or patination are commonly applied depending on functional or aesthetic requirements.
For bearing surfaces, honing or lapping produces the required surface texture for lubricant film formation.
(Select finishing and joining processes in consultation with the foundry to avoid galvanic compatibility issues and finish adhesion problems.)
7. 부식, wear and tribological performance
- 부식 저항: Tin bronzes such as C90300 exhibit excellent resistance in fresh and seawater environments and are commonly used for marine hardware and pump components.
Their tin content promotes a stable surface film and reduces susceptibility to certain localized corrosion mechanisms. - Tribology and bearing behavior: C90300 is valued for good conformability and embedability — under mixed or boundary lubrication it tends to accept small hard particles into the softer bronze matrix rather than scoring the harder shaft.
This makes it a favored material for bushings, plain bearings and sleeves running against hardened steel. Proper lubrication and surface finish are still necessary for long service life.
디자인 참고: for high-load rotating bearings consider tested bearing geometry, lubrication regime and possible use of lined or composite bearings if duty exceeds bronze’s capability.
8. Typical applications of UNS C90300 alloy
Common service areas where UNS C90300 is specified:
- 부싱, sleeves and plain bearings (hydraulic pumps, 기어 박스).
- Pump and valve components (사기꾼, 밸브 바디, 좌석) — especially in marine and water-handling equipment.
- 기어, worm wheels and small structural castings where castability and wear resistance are needed.
- 선박 fittings and propeller components where seawater corrosion resistance is required.
- Decorative castings and architectural elements where patina and aesthetics matter.
| Comparison factor | C90300 (Tin bronze) | C51000 (형광 청동) | C95400 (Aluminum bronze) | 리드 브론즈 (예를 들어, C93200, 일반적인) |
| 전형적인 구성 (wt%) | Cu ≈ 86–89; Sn ≈ 7.5–9; Zn ≈ 3–5; minor Fe/Ni | Cu ≈ 90–95; Sn ≈ 5–10; P ≈ 0.01–0.35 (추적하다) | Cu ≈ 78–88; Al ≈ 5–11; Fe/Ni/C (미성년자) | Cu + Sn base with PB additions ~1–4% (다양합니다), small Zn/Sn |
| Primary strengthening mechanism | 견고한 솔루션 & tin-rich phases from casting | 견고한 솔루션 + phosphide dispersion (피) — good spring/fatigue | 견고한 솔루션 + ordered phases; high strength via Al content | 견고한 솔루션; Pb acts as free-machining/soft phase for chip control |
| Typical as-cast UTS (MPA) | ~300–320 MPa | ~350–500 MPa (varies with alloy & 치료) | ~400–650 MPa (더 높은 강도) | ~220–350 MPa (depends on Pb, Sn content) |
Typical hardness (HB) |
~70–140 HB (프로세스에 따라 다름) | ~80–160 HB | ~120–220 HB (더 높은) | ~60–120 HB (softer due to Pb) |
| 입다 & bearing performance | Good conformability & embedability; widely used for bushings | Excellent fatigue and spring performance; good bearing alloys available | Excellent wear and high-load bearing capability | Good lubricity/embeddability; excellent machinability for bearing inserts |
| 부식 저항 (해수 / wet env.) | 매우 좋은 (marine service common) | 매우 좋음 (depends on Sn) | Very good to excellent (aluminum bronzes outstanding in seawater) | 보통의; leaded alloys can corrode in some environments; not preferred for seawater |
주파수 (foundry behavior) |
Very good — sand, 껍데기, 투자 | 좋은; available as cast or wrought; phosphor bronze often wrought | Good to fair — higher pouring temp, picky on melt control | 우수한 주파수; widely used for economical cast bearings/parts |
| 가공 가능성 | Moderate — improved by Sn for chip control | 좋은 (phosphor bronzes can be challenging if hard) | Moderate to difficult — hard alloys wear tools | 훌륭한 (lead dramatically improves free-cutting behavior) |
| Heat treatability / 경화 | Not precipitation-hardenable; anneal/stress relief only | Some variants respond to cold work; not classic age-hardening | Some alloys can be heat treated for strength (solution/aging) | Not age-hardening; properties controlled by composition and working |
일반적인 응용 프로그램 |
부싱, 펌프 부품, 밸브, 해양 피팅, worm wheels | 문장, 스프링, 전기 커넥터, wear components | 대형 베어링, 해양 프로펠러, high-load components, 기어 | Economical bushings, 피팅, low-cost machined parts, 대용량 구성 요소 |
| 상대 비용 | Moderate — tin is a premium element | 보통 - 높은 (phosphor and high Sn increase cost) | 더 높은 (Albronzes and alloying raise cost) | 낮추다 (leaded alloys are economical) |
| 주요 장단점 / selection note | Balanced choice for wear + 부식 + 주파수 | Choose when fatigue / spring performance or electrical properties matter | Choose for highest strength & severe wear / 캐비테이션 저항 | Choose where machining cost dominates and corrosive service is not critical; restricted in potable/water use |
10. 결론
UNS C90300 tin bronze is a 시간 테스트, high-value cast copper alloy that excels in balancing mechanical strength, 내마모성, corrosion durability, 그리고 주파수.
Its carefully engineered chemical composition and uniform microstructure deliver consistent performance in moderate-load, low-to-medium speed service environments, making it indispensable in marine, 유체 취급, mechanical power transmission, and general engineering sectors.
FAQ
What is the typical tin content in C90300?
Typical tin is ~7.5–9.0 wt% with copper as the balance; zinc is commonly present at ~3–5 wt%. Always check the mill certificate for the lot you receive.
Can C90300 be heat treated to increase strength?
No — C90300 is not a precipitation-hardening alloy.
Strength and ductility are primarily controlled through composition, section size and solidification rate; stress-relief anneals are used for dimensional stability.
Is UNS C90300 suitable for seawater service?
Yes — tin bronzes such as C90300 are routinely used in marine environments and pump components because of good seawater corrosion resistance and anti-fouling behavior relative to many steels.
What casting process should I specify?
사용 투자 캐스팅 for thin, detailed parts and tight tolerances; sand or shell casting for larger or economy parts.
Specify desired surface finish, tolerance band and NDT requirements up front.
