Burner Liner in a High Temperature Alloy: Can It Survive?

A 1.8 mm burner liner made from GH3536, a high temperature alloy, can survive a non-pressurized laboratory combustor. Oxidation, not strength, sets the ceiling at about 1,100 °C, and the part carries no sealing duty. A pressure vessel with the same geometry would need a different route.

What does combustion heat do to a high temperature alloy burner liner?

GH3536 is the Chinese designation for the nickel-chromium-iron-molybdenum high temperature alloy sold as Hastelloy X (UNS N06002, ASTM B435). The burner liner keeps useful strength to about 900 °C and resists oxidation to roughly 1,100 °C in clean combustion gas. Above that range the surface scales faster than a 1.8 mm wall can absorb.

The liner sees the flame directly at three quartz windows. Each opening cuts the wall and adds a hot edge, so the local metal runs hotter than the bulk gas. A printed wall handles that because the window frames, the cooling holes and the flange form one continuous shell, with no weld seam to oxidize first.

A welded sheet-metal liner is the usual alternative. Welding a 1.8 mm shell around three window frames leaves three heat-affected zones, and each one is a place where oxidation starts. The printed shell removes those seams but keeps the same alloy, which matters when the rig design already fixes GH3536.

Three numbers matter here. The wall is 1.8 mm and solution treatment runs at 1,180 °C for 1 h. The build chamber stays below 100 ppm oxygen, which keeps oxide inclusions out of the metal. The alloy itself is covered in our Hastelloy X 3D printing notes.

How does the printed wall handle thermal cycling?

The wall moves because the alloy has a thermal expansion coefficient of about 13.9 µm/m·K between 20 and 100 °C, and an open section has weak free edges. Printing does not lock the geometry; the heat treatments decide the final shape.

We print the liner upright with the long axis parallel to the recoater and support every overhang below 45°. Three 3 mm tie bars hold the window openings until solution treatment at 1,180 °C for 1 h has run. Hot isostatic pressing (HIP) then holds the part at 1,180 °C and 100 MPa for 3 h to close internal porosity.

Two blue-light scans bracket the thermal work. The first records the as-built profile before HIP; the second records the finished part after machining. Comparing the two shows what the heat cycle moved and what the cutter moved. The support and tie-bar rules follow our design rules for thin-wall superalloy parts.

Powder removal is part of the same cycle. Every hole is blown at 0.2 MPa and checked with an endoscope, then the liner is washed at 40 kHz for 15 min and vacuum packed. Residual powder in a cooling passage would change the flow field on the first run.

When is a printed burner liner the wrong choice?

Choose another route when the burner liner is a pressure boundary, when it needs a metal-to-metal seal, or when the gas stays above about 1,100 °C. A printed wall also stops making sense below 1.5 mm, where distortion and powder removal both get harder.

Size is the other limit. A single-piece shell much above 400 mm across no longer fits a 250 mm build chamber, and splitting it brings back the weld seams printing was meant to remove.

A cast or wrought liner with a machined window frame is the better answer when a standard fixes the alloy. It also wins when the wall is thicker than 3 mm or the part needs a certified pressure test. Printing earns its place when windows, holes and flanges sit in one thin shell.

GH3536 is not the only liner alloy. Cobalt-based Haynes 188 trades some strength for better thermal fatigue in cyclic service, and our Haynes 188 liner FAQ covers that comparison. The choice should follow gas temperature, cycle count and sealing requirement, not the printing process.

Send the drawing with the gas temperature, the cycle count and the window layout. We will confirm the wall, the heat treatment sequence and the machining allowance, and quote the printed liner through our superalloy 3D printing route.