CN101676424A

CN101676424A - Compacted graphite cast iron air cylinder sleeve and composition proportioning thereof

Info

Publication number: CN101676424A
Application number: CN200810196630A
Authority: CN
Inventors: 韦星野
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-09-15
Filing date: 2008-09-15
Publication date: 2010-03-24

Abstract

The invention discloses a Compacted graphite cast iron air cylinder sleeve and composition proportioning thereof. The air cylinder sleeve comprises the following elements: 3.2%-3.8% of C, 1.70%-2.30%of Si, 0.60%-0.80% of Mn, 0.20%-0.30% of Cr, 0.010%-0.020% of Mg, 0.01%-0.06% of S, 0.12%-0.34% of P, 0.02%-0.16% of Ce and 94.14%-92.22% of Fe. Finally, the processes such as pouring, rough machining, fine finishing and the like are performed according to the traditional technology.

Description

Compacted graphite cast iron air cylinder sleeve and composition proportion

Technical field

The present invention relates to cylinder sleeve and composition proportion, be specifically related to a kind of compacted graphite cast iron air cylinder sleeve and composition proportion.

Background technology

Cylinder is the space of gas compression, burning expansion, and piston motion is play the guiding role.The highest transient temperature of combustion gas can reach 2000 ℃～2500 ℃ in the combustion processes, and the highest pressure can reach 10MPa～15MPa, and the inwall of cylinder sleeve directly is subjected to the effect of high pressure, high-temperature fuel gas, and its outer wall is subjected to the cooling of water coolant.Greatly reach under the explosion pressure effect in inside and outside wall thermograde difference, cylinder sleeve is subjected to sizable thermal stresses and mechanical pressure, and piston makes cylinder-barrel surface be subjected to strong friction in its surperficial high speed to-and-fro movement.

Cylinder sleeve is the heart of engine, its material mostly is common grey iron or alloy gray cast-iron, research and development along with high-power engine, intensity to cylinder sleeve, wear resistance is had higher requirement, present alloy cast iron cylinder jacke, for satisfying the high-intensity requirement of cylinder sleeve, adopt than low-carbon-equivalent more, add more molybdenum, nickel, copper, alloying elements such as chromium, the dependence alloy strengthening satisfies the intensity and the wear resistance of cylinder sleeve, but material decision performance, because it is serious that the flake graphite in the graphitic cast iron isolates matrix, and its end is sharp-pointed, and when carry load, sharp-pointed end easily produces stress concentration, become foundry goods destructive starting point, the intensity of foundry goods and toughness are descended; If after the tensile strength of alloy gray cast-iron brought up to 350MPa, continue to improve its intensity and wear resistance, generally obtain as-cast bainite or take isothermal quenching to obtain bainite structure, will inevitably improve manufacturing cost greatly like this by adding alloying elements such as molybdenum, nickel, copper.

Summary of the invention

The invention provides a kind of compacted graphite cast iron air cylinder sleeve and composition proportion, because of being vermiform under light microscopic, the graphite of vermicular cast iron gains the name, its graphite form is short and thick, the end slyness, be evenly distributed, and surface irregularity, the end of circle can suppress the generation and the expansion of crackle, the disengaging of coarse surface-limited graphite.

The technology of the present invention solution is to contain following element in this cylinder sleeve: C 3.2%～3.8%Si 1.70%～2.30%Mn 0.60%～0.80% Cr 0.20%～0.30% Mg 0.010%～0.020% S 0.01%～0.06%P0.12%～0.34% Ce, 0.02%～0.16% Fe 94.14%～92.22%.

The composition proportion of cylinder sleeve of the present invention has the following advantages: 1. graphite form is short and thick, and the end slyness is evenly distributed, surface irregularity, and slick and sly end can effectively suppress the generation and the expansion of crackle, the disengaging of coarse surface energy restriction graphite.2. metallographic structure has a basket network structure, the basket network structure-reinforced the tissue of vermicular cast iron, make vermicular cast iron have the favorable mechanical performance, when bearing lubrication friction, magnesium iron basket network projection, the recessed and oil storage of the black eutectic cell of wriggling, thus make vermicular cast iron have the good wear performance.3. the graphite shape of this uniqueness is compared with graphitic cast iron, can significantly improve tensile strength, fatigue strength, Young's modulus and wear resisting property.4. near the good castability of graphitic cast iron.

Description of drawings

Accompanying drawing is composition proportion figure of the present invention.

Embodiment

Example 1: carry out melting by the composition proportion batching, wherein C 3.2%; Si 1.70%; Mn0.60%; Cr 0.20%; Mg 0.010%; S 0.01%; P 0.12%; Ce 0.02%; Fe 94.14%.At last with traditional technology pour into a mould, operation such as roughing, precision work.

Example 2: carry out melting by the composition proportion batching, wherein C 3.8%; Si 2.30%; Mn 0.80%; Cr 0.30%; Mg 0.020%; S 0.06%; P 0.34%; Ce 0.16%; Fe 92.22%.At last with traditional technology pour into a mould, operation such as roughing, precision work.

Example 3: carry out melting by the composition proportion batching, wherein C 3.5%; Si 2.0%; Mn 0.70%; Cr 0.25%; Mg 0.015%; S 0.035%; P 0.23%; Ce 0.09%; Fe 93.18%.At last with traditional technology pour into a mould, operation such as roughing, precision work.

Claims

1. compacted graphite cast iron air cylinder sleeve and composition proportion is characterized in that: contain following element in this cylinder sleeve: C 3.2%～3.8%Si 1.70%～2.30% Mn 0.60%～0.80% Cr 0.20%～0.30% Mg 0.010%～0.020% S0.01%～0.06% P, 0.12%～0.34% Ce, 0.02%～0.16% Fe 94.14%～92.22%.