Best IN939 Powder for 3D Printing in 2023

Overview of IN939 Powder for 3D Printing

IN939 is a high-performance nickel-based superalloy powder designed for additive manufacturing of critical components needing exceptional mechanical properties at high temperatures. This article provides a comprehensive guide to IN939 powder for 3D printing applications across aerospace, automotive, energy and industrial sectors.

Key aspects covered include IN939 composition, properties, print parameters, applications, specifications, suppliers, handling, inspection, comparisons to alternatives, advantages and limitations, and frequently asked questions. Quantitative data is presented in easy-to-reference tables.

Composition of IN939 Powder

IN939 has a complex precipitation hardening alloy composition:

Элемент	Весовые %	Цель
Никель	Баланс	Principal matrix element
Хром	15 – 18	Коррозийная устойчивость
Алюминий	3.8 – 4.8	Упрочнение осадками
Титан	0.9 – 1.4	Упрочнение осадками
Кобальт	12 – 15	Solid solution strengthening
Тантал	3.8 – 4.8	Carbide former
Углерода	0.05 – 0.15	Carbide former
Бор	0.006 – 0.012	Grain boundary strengthener

Trace quantities of zirconium, magnesium and sulphur are also added for enhanced properties.

Properties of IN939 Powder

IN939 possesses an exceptional combination of properties:

Имущество	Описание
высокая прочность	Excellent tensile and creep rupture strength up to 1050¡«C
Термическая стабильность	Strength maintained up to 1000¡«C
Creep resistance	High stress-rupture life at high temperatures
Коррозийная устойчивость	Forms protective Cr2O3 oxide scale
Thermal fatigue resistance	Resists cracking during thermal cycling
Phase stability	Microstructure stable after prolonged exposures
Коррозионная стойкость	Resistant to hot corrosion, oxidation, sulfidation

The properties enable use under extreme thermal and mechanical loads.

3D Printing Parameters for IN939 Powder

Typical AM processing parameters for IN939 include:

Параметр	Typical value	Цель
Layer thickness	20-50 Ãœm	Resolution vs build speed
Laser power	250-500 W	Sufficient melting without evaporation
Scan speed	800-1200 mm/s	Density vs production rate
Hatch spacing	100-200 Ã×m	Mechanical properties
Support structure	Минимум	Easy removal
Hot isostatic pressing	1160¡«C, 100 MPa, 3h	Eliminate porosity

Parameters are optimized for attributes like density, microstructure, build rate, and post-processing requirements.

Applications of 3D Printed IN939 Parts

Additively manufactured IN939 components serve critical applications including:

Промышленность	Компоненты
Аэрокосмическая отрасль	Рабочие лопатки турбин, сопловые лопатки, камеры сгорания
Выработка электроэнергии	Hot gas path parts, heat exchangers
Автомобильный	Turbocharger wheels, valves
Химическая обработка	Pumps, valves, reaction vessels

Benefits over conventionally processed IN939 include complex geometries and reduced lead time.

Specifications of IN939 Powder for 3D Printing

IN939 powder for AM must meet exacting specifications:

Параметр	Спецификация
Размер частиц	15-45 Ã×m typical
Форма частиц	Spherical morphology
Кажущаяся плотность	> 4 g/cc
Плотность при утрамбовке	> 6 g/cc
Скорость потока холла	> 23 sec for 50 g
Чистота	>99.9%
Содержание кислорода	<100 частей на миллион

Tighter tolerances, custom size distributions, and controlled impurity levels available.

Suppliers of IN939 Powder

Reputable suppliers of IN939 powder include:

Поставщик	Местоположение
Sandvik Osprey	Соединённое Королевство
Carpenter Additive	США
Praxair	США
AP&C	Канада
Эрасталь	Швеция
AMETEK	США

Pricing for IN939 powder ranges from $110/kg to over $220/kg based on quality and order volume.

Handling and Storage of IN939 Powder

As a reactive powder, careful handling of IN939 is needed:

• Store sealed containers in a cool, inert atmosphere
• Prevent contact with moisture, oxygen, acids
• Use properly grounded equipment
• Avoid dust accumulation to minimize explosion risk
• Local exhaust ventilation recommended
• Wear appropriate PPE while handling

Proper techniques and controls prevent IN939 powder oxidation or contamination.

Inspection and Testing of IN939 Powder

IN939 powder is validated using:

Метод	Parameters Tested
Гранулометрический анализ	Распределение размера частиц
Сканирующая электронная микроскопия	Particle morphology
EDX	Chemistry and composition
XRD	Phases present
Pycnometry	Плотность
Скорость потока холла	Текучесть порошка

Testing per applicable ASTM standards ensures batch consistency.

Comparing IN939 to Alternative Alloy Powders

IN939 compares to other Ni-based superalloys as:

Сплав	Высокотемпературная прочность	Цена	Возможность печати	Пластичность
IN939	Отличный	Высок	Отличный	Низкий
IN738	Хорошо	Средний	Отличный	Средний
IN718	Справедливо	Низкий	Хорошо	Отличный
Хастеллой® X	Отличный	Высок	Справедливо	Средний

For balanced properties and processability, IN939 supersedes alternatives like IN718 or Hastelloy X.

Pros and Cons of IN939 Powder for 3D Printing

Преимущества	Минусы
Exceptional high temperature strength	Expensive compared to IN718
Excellent oxidation and creep resistance	Significant parameter optimization needed
Complex geometries feasible	Limited room temperature ductility
Faster processing than cast/wrought	Controlled storage and handling environment
Comparable properties to cast alloy	Difficult to machine after printing

IN939 enables high-performance printed parts but with higher costs and controlled processing needs.

Frequently Asked Questions about IN939 Powder for 3D Printing

Q: What particle size range works best for printing IN939?

A: A particle size range of 15-45 microns provides good flowability combined with high resolution and density. Finer particles below 10 microns can improve density and surface finish.

Q: Does IN939 require any post-processing after 3D printing?

A: Post processes like hot isostatic pressing, heat treatment, and machining are usually needed to eliminate porosity, relieve stresses, and achieve final tolerances and surface finish.

Q: What precision can be achieved with IN939 printed parts?

A: After post-processing, dimensional accuracy and surface finish comparable to CNC machined parts can be achieved with IN939 AM components.

Q: Are support structures necessary for printing IN939 powder?

A: Minimal supports are recommended for complex channels and overhangs to prevent deformation and facilitate easy removal. IN939 powder has good flowability.

Q: What alloy powder is the closest alternative to IN939 for AM?

A: IN738 is the closest alternative in terms of balanced properties and maturity for additive manufacturing. Other alloys like IN718 or Hastelloy X have some trade-offs.

Q: Is IN939 compatible with direct metal laser sintering (DMLS)?

A: Yes, IN939 is readily processable by major powder bed fusion techniques including DMLS along with selective laser melting (SLM) and electron beam melting (EBM).

Q: What density is achievable with 3D printed IN939 components?

A: With optimized parameters, densities over 99% are achievable, matching properties of traditionally processed IN939 products.

Q: How do the properties of printed IN939 compare to cast alloy?

A: Additively manufactured IN939 exhibits comparable or better mechanical properties and microstructure compared to conventional cast and wrought forms.

Q: What defects can occur when printing with IN939 powder?

A: Potential defects are cracking, distortion, porosity, surface roughness, incomplete fusion etc. Most can be prevented by proper parameter optimization and powder quality.

Q: Is hot isostatic pressing (HIP) mandatory for IN939 AM parts?

A: HIP eliminates internal voids and improves fatigue resistance. For less demanding applications, heat treatment alone may suffice instead of HIP.