The box type resistor muffle furnace is widely and deeply used in the metal industry, with its core value reflected in high temperature processing capability, precise temperature control, and multifunctionality, which can meet the full chain needs of metal materials from research and development to production. The following analysis will be conducted from three aspects: typical application scenarios, technological advantages, and industry cases:
1. Typical application scenarios
Metal heat treatment
Annealing: By slowly heating to the critical temperature (such as carbon steel 720-750 ℃) and holding for a certain period of time, the internal stress of the metal is eliminated and the machinability is improved. For example, after annealing, the hardness of 45 # steel decreases to HB180-200, making it easier for subsequent turning, milling, and other operations.
Quenching: Heating the metal to the austenitizing temperature (such as 830-860 ℃ for GCr15 bearing steel) and rapidly cooling it to form a martensitic structure, significantly increasing its hardness. After quenching, the hardness of GCr15 reaches HRC 60-65, and the wear resistance is increased by more than three times.
Tempering: After quenching, the toughness is adjusted by low-temperature heating (such as 150-250 ℃) to reduce brittleness. For example, the elastic limit of spring steel increases by 20% after tempering, while reducing the risk of fracture.
Metal melting and purification
Precious metal purification: Under vacuum or inert atmosphere, the metal is melted at high temperature (such as 1200-1400 ℃) to separate impurities. For example, in the process of gold purification, the muffle furnace can remove impurities such as silver and copper, and the purity can be increased to over 99.99%.
Alloy preparation: Heat different metals in proportion above their melting points (such as aluminum alloy 660 ℃, copper alloy 1083 ℃), mix and cool to form. The uniform heating characteristics of the box type resistor muffle furnace ensure uniform alloy composition and stable performance.
Research and development of metal materials
Phase transition research: By controlling the heating rate (such as 5-10 ℃/min) and holding time, observe the phase transition process of metals at different temperatures. For example, titanium alloys can form a fine-grained structure and improve strength and toughness by rapidly cooling after being insulated in the beta phase region (above 882 ℃).
Mechanical performance testing: Standard specimens (such as tensile specimens and impact specimens) are treated in a muffle furnace and subjected to tensile, impact, and other tests to evaluate material properties. For example, after quenching at 900 ℃ and tempering at 650 ℃, 40Cr steel has a tensile strength of 1000 MPa and an elongation of 15%.
2. Technical advantages
High temperature processing capability
The maximum temperature of the box type resistor muffle furnace can reach 1700 ℃, far exceeding conventional heat treatment equipment (such as salt bath furnace 800-900 ℃), and can process high melting point metals (such as tungsten 3410 ℃, tantalum 2996 ℃) and their alloys.
Accurate temperature control
Equipped with PID intelligent temperature control system, temperature fluctuation ≤ ± 5 ℃, supporting multi-stage program temperature control (such as 30 stages). For example, stainless steel solution treatment requires insulation at 1050-1100 ℃ for 30 minutes, and a muffle furnace can accurately achieve this process requirement.
Atmosphere protection
Some models are equipped with inlet and outlet ports, which can be filled with inert gases such as argon and nitrogen, or reducing gases such as hydrogen to prevent metal oxidation. For example, when argon gas is introduced during heat treatment of titanium alloy, the thickness of the surface oxide layer can be controlled within 0.1 μ m.
Uniform heating
Using ceramic fiber or alumina furnace, with low heat capacity and good thermal conductivity, combined with modular heating elements, to ensure temperature uniformity within the furnace of ≤± 10 ℃. For example, during heat treatment of large metal parts (such as gears with a diameter of 500mm), the performance difference of each part is ≤ 5%.
3. Industry Cases
Case 1: Heat treatment of high alloy steel
Equipment: SX2-12-10 box furnace (1200 ℃).
Process: Heat high alloy steel (such as 30CrMnSiA) to 880 ℃ for 2 hours, then oil quench and temper at 650 ℃.
Effect: Hardness reaches HRC 45-50, impact toughness ≥ 50 J/cm ², meeting the performance requirements of aerospace components.
Case 2: Copper Alloy Smelting
Equipment: XH1L-14 High Temperature Furnace (1650 ℃).
Process: Copper (Cu), zinc (Zn), and aluminum (Al) are added to the furnace in proportion, protected by argon gas, and heated to above 1083 ℃ for melting and mixing.
Effect: The prepared brass (H62) has a tensile strength of 400 MPa and an elongation of 20%, and is used in the manufacturing of valves, pipe fittings, and other products.
Case 3: Metal Powder Sintering
Equipment: Tube furnace (1200 ℃).
Process: Fill 316L stainless steel powder into a graphite mold, degreasing at 900 ℃ and sintering at 1250 ℃ in a hydrogen atmosphere.
Effect: The sintered body has a density of 7.8 g/cm ³ and a porosity of ≤ 1%, making it suitable for biomedical applications such as artificial joints and dental implants.