Melt flow rate adjustment system and method of multi-component radial functional-gradient-material equipment

An adjustment method of a melt flow rate adjustment system of multi-component radial functional-gradient-material equipment, characterized in that,

• the adjustment system includes a raw material storage tank, a mixing funnel, a screw smelting machine, a centrifugal casting machine, a temperature sensor and a control platform, wherein,
• the raw material storage tank is used to store raw materials for preparing the multi-component radial gradient material;
• the mixing funnel is used to mix materials entering from the storage tank and control the raw materials to enter the screw smelting machine at different speeds;
• the screw smelting machine is used to melt the raw materials with a different chemical ratio in the mixing funnel in a feeding order to prevent the long-range diffusion of a melt, and to control outflow at a suitable speed;
• the centrifugal casting machine is used to solidify the melt into a radial functional gradient material by a centrifugal casting style;
• the temperature sensor is used to monitor temperature of an outer surface of a centrifuge cavity of the centrifugal casting machine during centrifugal casting, and transmit the temperature to the control platform;
• the control platform is used to determine an optimal flow rate of the melt at an end of a screw rod in combination with real-time data fed back from the temperature sensor, and to feedback to a feeding end;
• the method specifically includes the following steps of:
• S1) selecting the required raw materials according to ingredients and pipe wall-thickness of the multi-component radial functional-gradient-material prepared by design requirement, and putting each of the raw materials in each raw material storage tank for use, respectively;
• S2) the control platform determining a flow rate V of the melt according to the ingredients and pipe wall-thickness of the multi-component radial functional-gradient pipe material prepared by requirements, and transmitting the flow rate V to the mixing funnel, the screw smelting machine and the centrifugal casting machine;
• S3) the mixing funnel receiving a control platform instruction, batching according to the ingredients and pipe wall-thickness of the multi-component radial functional-gradient pipe material, and mixing evenly, and then delivering the raw materials to the screw smelting machine;
• S4) the raw materials entering a melting cavity of the screw smelting machine, being separated by the screw rod that is close to an inner wall of the melting cavity and rotates vertically downwards for performing gradient melting, the control platform regulating and controlling melting temperature and rotation speed R of the screw rod to make the melt with ingredients continuously varying being transferred to the centrifugal casting machine at an optimal centrifugal pouring speed, that is, the melt flow rate V;
• the rotation speed R of the screw rod in S4) is determined by the following formula (4), which is as follows:
• R
• =
• ρ
• j
• ′
• ⁢
• π
• [
• C
• j
• ′
• (
• T
• j
• ⁢
• 0
• -
• T
• jS
• )
• +
• L
• j
• ′
• ]
• ⁢
• (
• D
• e
• 2
• ⁢
• cos
• ⁢
• Φ
• )
• ⁢
• A
• ⁡
• (
• τ
• )
• 2
• ⁢
• τ
• 2
• (
• b
• j
• +
• b
• S
• )
• ⁢
• (
• T
• ij
• -
• T
• j
• ⁢
• 0
• )
• ⁢
• (
• D
• B
• 2
• -
• D
• S
• 2
• )
• ⁢
• B
• ·
• A
• runner
• ,
• (
• 4
• )
• in the formula,
• R is a rotation speed of the screw rod, Φ is a helix angle of thread,
• DS is a diameter of the screw rod, DB is a diameter of sleeve-port;
• B is an axial distance among screw edges, and De is a diameter of feeding port,
• ρj′ is bulk density according to density of each of the raw materials, j=A, B, C . . . N, representing various ingredient castings, and the unit of ρj′:
• g/cm3,
• bj is heat storage coefficients of the casting,
• bs is heat storage coefficient of internal environment of the centrifuge cavity,
• Cj′ and Lj′ are an actual specific heat capacity and an actual crystallization latent heat value of mixed multi-component gradient material of each layer, respectively,
• Tjo is an initial temperature of casting;
• TjS is an actual liquidus temperature of each ingredient melt,
• Tij is temperatures of an interface between a casting mold and the casting, an interface between various ingredient casting interfaces, and an interface between the casting and internal environment of the centrifuge cavity during an unstable heat conduction process in a casting cavity,
• ij=OA, AB, BC . . . NS, O is the casting mold material, S is internal environment of the centrifuge cavity, and
• A(τ) is an internal surface area of the pipe wall at time τ, and Arunner is a cross-sectional area of a runner, and
• S5) the melt entering the centrifugal casting machine at the flow rate V, and then filling and solidifying in the casting cavity under the action of centrifugal force, in combination with a water-cooling device outside the casting cavity to achieve an efficient production mode of instant solidification when entering to prevent the melt from mixing, a thereby forming the multi-component radial functional-gradient material with ingredients continuously varying.