Material properties and process analysis of steel alloys

1. Overview of steel alloys
Steel alloy is based on steel base (the content is usually ≥50%), and is the predecessor of high-temperature alloy system in the formation of alloying elements such as steel, blue, iron, iron, iron and so on. Due to its unique high temperature strength, corrosion resistance and air resistance ability, it has an irreplaceable position in aerospace, energy and chemical industry, nuclear industry and other leading environmental areas. Typical tiles include Inconel series, Hastelloy series, Monel alloy, etc.

2. Core characteristic analysis
1. High temperature performance
Working temperature range: Possible 540-1200℃ range holding constant mechanical performance, partial plate number (like Inconel 718) holding capacity below 700℃ 650MPa resistance

Strengthening mechanism: γ' phase (Ni3(Al,Ti)) precipitation strengthens, solid solution strengthens, and crystal boundary dispersion strengthens.

Peristaltic resistance: under high temperature loading, steel base alloy base peristaltic change speed ratio ratio of non-steel steel low 2-3 quantity line

2. rot resistance
Carbonization rot: Cr element formation dense Cr2O3 carbonization film (thickness approximately 2-5μm), effective distance below 1000℃, oxidation dispersion

Acidic environment: Mo-containing alloy (like Hastelloy C-276) corrosion rate in organic acid <0.1mm/year, more than 20 times that of Wongyu 316L non-ferrous steel

Strength Corrosion Explosion (SCC): Fe content ≤10%, S/P quality ＜50ppm SCC ability
3. Typical usage area
1. aviation astronomy
The heating end parts of the moving machine (leaves, combustion chamber)

Fire torch moving machine injection device (accepted 3000℃ instantaneous heating)

2. Energy area
Nuclear steam generator ＠heat tube (service life > 40 years)

Combustion machine transfer stage (heat barrier layer base material)

3. Chemical equipment
Acidic oil pipe (H2S branch > 0.3MPa)

PTA reactor stirrer (contact 100℃ acetic acid)

4. Processing challenge and solution plan
1. work hardening
Improved cutting speed: Line speed control 15-30m/min, thread flow 0.05-0.15mm/track

Cutting tool selection: TiAlN curved hard quality alloy cutting tool with excellent tip, back angle increased to 10-15°

2. Enclosure
Arc fire protection, body purity demand 99.999%, temperature limit below 150℃

After heating: Inconel 718 demand running 720℃×8h time efficiency removal residual force

3. surface texture
Electrolysis: Ra < 0.2 μm surface obtained in H3PO4:H2SO4=3:1 electrolytic solution, electric current density 20A/dm²

Al-Si layer: 50μm layer formed by continuous CVD process, heat treatment temperature 200℃