In shaped refractories, bricks are the most intuitive but also the easiest to be misled by "grade." The real differences are the combination of refractoriness, load softening, thermal shock resistance, slag resistance, and volume stability.

[Image: appearance and cross-section collage of three bricks]

01 Fireclay brick: the basic option, strong on cost and applicability

• Features: versatile, easy to build, low cost
• Suitable for: moderate temperatures, non-extreme conditions, paired with insulation structures

02 High-alumina brick: a step up in strength and refractoriness

• Features: higher alumina content, stronger refractoriness and hot strength
• Suitable for: hot zones, scouring or load-bearing areas (still depends on slag and thermal shock)

03 Mullite brick: a route for high-temperature and dimensional stability

• Features: more stable high-temperature structure, usually better volume stability (depends on material system and firing control)
• Suitable for: high-temperature zones, areas more sensitive to size stability and long-term operation

04 Do not choose bricks only by "refractoriness"

What actually determines service life on site is often:

• Slag acidity/alkalinity and corrosion mode
• Thermal cycling frequency (thermal shock)
• Structural stress and masonry quality (mortar joints, expansion joints, staggered joints)

Xinhui typically does not push a single material. It recommends combinations by zone: a more stable system for the hot-face load-bearing layer, a more cost-effective system for the backup layer, spending where it matters.

[Image: furnace zoning material diagram: hot face/transition/insulation]